Hi there;
This is a quick list of programs and other stuff that is very usable for game programming which is offered up free of charge and free of royalties.
If you know a tool or other thing that is handy for game programmers, please don't hesitate to add it to this list. Nothing it hosted here, we only link to stuff.
Please note that some programs may be marked as 'Strong Copyleft'. This means that the license of that tool or product may require you to make the game you create free or to copy the license of the product you chose. The GPL is the most famous example of that. So I really recommend to check the licenses before using the stuff I link to.