HotCocoa is a project mainly written in OBJECTIVE-C and C, it's free.
IDE for iOS!!
HotCocoa is (or will become) a super awesome, well designed, IDE, made just for iOS devices. Planned features include:
Although ambitious, I think making this available will finally mature the iOS platform into one that can sustain itself (ie. be able to write programs for itself), and that in itself can become something really amazing!