The web is abundant with interesting sites, on this page I will try to list but a few that I have found interesting or useful.
I am recommending everyone to try a GNU/Linux distribution (preferably a live disc), for several reasons.
I am a firm believer in FOSS, due to it's superior development model, the ROI, TOC etc. and because it is easy, made by IT professionals and enthusiasts, because it is safe and because it is FREE, and often Gratis, imagine GNU/Linux is Legal to download, copy and distribute.
With distros like Debian/Ubuntu you have more than 65.000 available pieces of software.
See a whole range of distributions here: Distrowatch.
www.osalt.com Find open source software alternatives to well-known commercial software.
For beginners I recommend you check out Ubuntu - It is super user friendly and is a so called Live disc. i.e. run without installing, if it works and you like it then you can proceed to install. For those who are a little more battle hardened go to the Debian homepage.
Just to point to a few high quality products I recommend you try an astronomy program called stellarium.org, an animation studio called 3D Blender , a photo manipulation program called Gimp, I could go on but urge you to go exploring in stead (elsewhere on the page you can find links to tutorials to get you started with GIMP and Blender).
Finding help and support is a breeze. On linuxquestions.org you have several hundred thousand would be supporters who freely share experiences and offer highly qualified advice free of charge. I adamantly recommend this site.
You can find more computer relates links further down this page.
Wikipedia - Everybody's favorite (well maybe not everyones) the free encyclopedia that anyone can edit. As of 23 October 2008 - 2,596,113 articles in English - and oodles of them in other languages as well.
thefreedictionary - A truly brilliant free dictionary and more.
As a firm believer in innovation I believe software patents stifle innovation and exist only to cement monopolies, and if you want to know more about the subject I suggest you visit http://stopsoftwarepatents.org/.
IT-Political Association of Denmark I'd say is a danish equivalent to The Electronic Frontier Foundation (EFF) which in turn is an international non-profit advocacy and legal organization based in the United States.
Like the EFF IT-Political Association of Denmark keeps a keen eye on issues like, Intellectual Rights, Patents on Software, Privacy and freedom of speech, Censorship and filtering - Which has landed them between a rock and a hard place as big brother rolls across the free world.
EFF - For more information on EFF please visit them.
I have enjoyed several of the courses from W3Schools.
http://w3schools.com/ - Giant overview over self learning courses (I mention a few on this page)
http://w3schools.com/tcpip/default.asp - TCP/IP inner workings of your network and the internet revealed.
Version 2's Android Academy (Danish)
Home of Roger Cadenhead - The creator of a 24'hrs marvelous java course.
Linux Howto's - A comprehensive list of Linux howto's - A regular gold mine.
Something of interest to those who are trying out Linux on www.tldp.org http://www.tldp.org/HOWTO/Multiboot-with-GRUB.html
stackoverflow.com A programming Q&A site created by Jeff Atwood and Joel Spolsky in 2008 - very open and easy to use, no signup, no fees etc. very very nice, and super simplistic approach to a question forum, speedy answers if asking concise questions.
LiveCode LiveCode is a very powerful easy to use cross platform application development framework that has been released under the GPL using it you will be able to write once deploy to many platforms simultaneously in one go you can create applications for Android, Linux, Apple IOS, Windows.
I highly recommend you give this environment a look - and there are a lot of promising add ons coming during the year. You can read more about upcoming development both on the Kickstarter campaign site as well as on RunRev's own page http://www.runrev.com/
Here a great beginners course https://sites.google.com/a/pgcps.org/livecode/home teaching you to create games in LiveCode.
http://eclipse.org - for developers. http://bluejay.org an IDE for beginners.
A GUI editor for Eclipse - Uses regular java to generate GUI's http://www.cloudgarden.com/jigloo/.
http://en.wikipedia.org/wiki/Operating_system - Operating systems, tons of links
http://en.wikipedia.org/wiki/Harddisk - Harddisks
http://en.wikipedia.org/wiki/RAID - RAID technology
http://en.wikipedia.org/wiki/Binary_numeral_system - Binary numbers
http://en.wikipedia.org/wiki/Hexadecimal - Hexadecimal numbers
http://www.jorgepena.be/binary-and-hexadecimal/ - Binary and Hex tutorial.
Binary counting made fun - An instructional video by a Computer Science Professor at Rutgers University. United States. He has made quite a few of these - Priceless.
http://w3schools.com/html/default.asp - HTML - Homepage Syntax, step by step instructions.
http://w3schools.com/sql/default.asp - SQL - Standard Query Language, for anyone who needs to work with Databases.
http://www.informit.com/library/content.aspx?b=STY_Java2_24hours&seqNum=2&rl=1 - 24 one hour lessons JAVA. A fantastic course.
The Java Developers Almanac 1.4 - Fantastic site with tonnes of examples.
Learn Python - This Youtube based series “Python Programming Tutorial”, takes you through a step by step introduction to the Python language, easy to understand, clear and comprehensive.
Python GUI programming tutorial - Create an egg timer in a 30 minutes lesson
UML - Unified modeling language, is a design tool for application design.
http://www.comptechdoc.org/independent/uml/begin/index.html - another view at UML/RUP
Read more at IBM's developerworks website and at Wikipedia on UML
http://www.javaworld.com/javaworld/jw-10-2005/jw-1003-mvc.html - The MVC pattern —> SUPER IMPORTANT ! ←–
http://www.javaworld.com/javaworld/jw-04-2003/jw-0425-designpatterns.html - Singleton pattern —> QUITE CLEVER ←–
http://en.wikipedia.org/wiki/Extreme_Programming - eXtremeProgramming (programming methodology).
http://en.wikipedia.org/wiki/SCRUM - SCRUM (programming methodology)
http://en.wikipedia.org/wiki/DSDM - Dynamic Systems Development Method - (programming methodology)
http://en.wikipedia.org/wiki/Feature_Driven_Development - Feature Driven Development - (programming methodology)
Convert your 3D models into paper - DXF2Papercraft at http://dxf2papercraft.sourceforge.net does the “planning” work, you cut and glue.
Free tools for the 3D enthusiasts
blender.org - 3D Game engine & Animation studio
http://www.sourcefilmmaker.com/ - A steam based moviemaking tool
BLENDER:
http://www.linuxhaxor.net/25-tutorials-to-get-you-started-with-blender/
http://www.youtube.com/watch?v=3ZxEhZwCfh0&context=C39b9f82ADOEgsToPDskIyW-4AJlh4oFBFpI8iWEzq - Character control
http://www.youtube.com/watch?v=A5r2dNmctFQ&feature=related - make character jump
www.youtube.com/watch?v=SRXoFLG9XR8 - Blender 3D tutorial - 3rd Person shooter #1 - The above two in one tutorial… with a slight difference
http://www.youtube.com/watch?v=SRXoFLG9XR8&list=PL1836D2AD80A14969&index=1&feature=plpp_video - Blender 3D tutorial - 3rd Person shooter - playlist
http://www.youtube.com/watch?v=3lDl9L3CzdI - how to make your character shoot in Blender3D
http://www.youtube.com/watch?v=eyDp7vn8iAg&context=C36c9da6ADOEgsToPDskJ0IIC9yy_WMIQIex6Whf_j - adding 3D texts to game
http://arnaud.ile.nc/sce/home - tool to create Blender3D cities with a single click
http://www.youtube.com/watch?v=aVWz96erinc&feature=related - “The Real Way” to Fire a Gun in Blender
http://www.youtube.com/watch?v=iG2qvhcx7jU&feature=related - Blender follow system… perfect for those zombie games ;)
www.youtube.com/watch?v=H9bKw-14_Yw&feature=related - How to make and kill an enemy on blender
www.youtube.com/watch?v=VIsFlG46-wI - Basic Enemy AI (No python) - Blender Game Tutorial
www.youtube.com/watch?v=fAGjzdh4OKY - Blender 2.5 FPS Tutorial - Part 1
www.youtube.com/watch?v=SRXoFLG9XR8 - Blender 3D tutorial - 3rd Person shooter #1
http://www.katsbits.com/tutorials/blender/import-google-sketchup-kmz-models.php - Importing Google SketchUp files into Blender 3D
http://cgtextures.com/ - a load of textures
www.blenderguru.com/videos/how-to-create-a-lightning-storm
www.blenderguru.com/videos/how-to-make-a-realistic-asteroid
www.youtube.com/watch?v=ows2QTiMRPg&feature=related Blender-Converting 2D Image to 3D Object
www.youtube.com/watch?v=Qr7x3AxVYQQ&feature=related Blender Split Screen Game Tutorial
www.youtube.com/watch?v=dPX4QNjRmbc&feature=related - Weapon Switch Tutorial for Blender 3D
www.youtube.com/watch?v=4deJ5wDIBR8 - Special Blender Tutorial - Using the APPEND function (multiple blend files for one final big blend)
www.youtube.com/watch?annotation_id=annotation_431767&feature=iv&src_vid=mGjqEM6xVY4&v=OAsD47aRndk - Blender 3d Tutorial: Creating a simple character
www.youtube.com/watch?v=dn-hQKImPjc - Blender Tutorial Splitting Screen to View multiple angles
www.youtube.com/watch?v=PeWvVk69Whs&feature=related - Blender Tutorial - How to Merge Two Objects Together
http://www.youtube.com/watch?v=4j9fnps7IxA&feature=related - Creating landscapes nice and easy
UNITY 3D
http://unity3d.com/learn/tutorials/projects/roll-a-ball/introduction ← UNITY's OWN ROLL A BALL GAME - Learn to make and publish a
game in less than 2 hrs
Add to complexity - 2 hrs more by leafing through a Brackeys course on Unity 3D - A ball game as well including Jump and more advanced things like particle systems / respawn / Sound etc.
1 https://www.youtube.com/watch?v=g5QFW12utdU - BASIC SETUP
2 https://www.youtube.com/watch?v=N49cfP-MWJA - MAIN (controller)
3a https://www.youtube.com/watch?v=PazLGgeFkHI - JUMP
https://www.youtube.com/watch?v=m8VPHAs0F8w - CAMERA
4 https://www.youtube.com/watch?v=o0iaD_Li5xk - LEVEL DESIGN & TEXTURES
5 https://www.youtube.com/watch?v=atyG6XfU3aI - SHADOWS and RESPAWN
6 https://www.youtube.com/watch?v=kq1HsljPzLc - QUALITY SETTINGS
7 https://www.youtube.com/watch?v=1zF2W8JxFK4 - Collectibles
8 https://www.youtube.com/watch?v=gQRCK0znUzo - ANIMATION
9 https://www.youtube.com/watch?v=f6s9RO8pZZc - PARTICLES
10 https://www.youtube.com/watch?v=p9Uk9Ngyqaw - SCORE
11 https://www.youtube.com/watch?v=xafs9uljpqE - SOUND
12 https://www.youtube.com/watch?v=pF5KSTBPy4Y - GRAPHICS (blender import)
13 https://www.youtube.com/watch?v=yicdpF5YnTo - MUSIC MANAGER
14 https://www.youtube.com/watch?v=unfJfs_ok-Q - PHYSICS
15 https://www.youtube.com/watch?v=1z5aAK0rN-4 - MAIN MENU
16 https://www.youtube.com/watch?v=JIlKuZffmwE - MAIN MENU (Continued)
17 https://www.youtube.com/watch?v=1H_E-GsoNe4 - CHECKPOINTS
https://www.youtube.com/watch?v=Rxk092cLLyo Inventory and extension - Free
Inkscape - A vector graphics suite, a really neat program. Completely free in multiple senses.
Ever been in the situation that a URL was too long to send in IM or via twitter or other means ?
TINYURL - is one possible answer - A no log in service that abbreviates url's to almost nothing, and it is a free service.
Twitter - Tweet away to create a following, build a fan base, promote your thoughts or products.
Addthis - An incredible site that allows you to create buttons that allow your visitors to add your site to thousands of social bookmarking sites, in 10 seconds flat, no log in required.
A section I should have started long ago and that will likely grow into its own page
http://news.bbc.co.uk/2/hi/science/nature/8466493.stm - The most magnificent crystal caves I've ever seen.
http://singularityhub.com - The Future Is Here Today...Robots, Genetics, AI, Longevity, Singularity
Totally gridbag - I suggest any upcoming JAVA guru to get into gridbag and spring layout - But Beware :)