If you find some resources online and would like to share them with the community, please do so here!
This is a library created by me, AJF, that allows you to use a more object-oriented style of creating and using objects in DFSDK. (it is a thin wrapper round the DFSDK API)
Image Editing / Creation
GIMP is a cross platform, open-source image manipulation program that can export to the PNG file format. It bears many similarities to Adobe Photoshop.
Sound / Audio
Sound Editing / Recording
Audacity: Audacity is an open source sound recording/editing software. It can handle a variety of sound formats, including WAV and MP3(using the LAME MP3 encoder). I've used it for sound editing as well as for recording instruments.
Lita is a free and open source SQLite database administration tool for Windows, MacOSX and Linux.
Every year these guys do this cool 48-hour game creation challenge where each 1-2 member group has 48 hours to make the best iPhone game possible, pertaining to a certain theme. It says that any method of creation is available, but you do have to register their iPhone's UDID.
- 1001 Free Fonts: 1001 Free Fonts has a very large selection of fonts with the vast majority being 100 percent free with no licensing stipulations. The site is also fairly ad-free, aside from their own internal promotions.