For those of you interested in programming for PalmOS, there is a free compiler called PRC-Tools (which is based on GCC) which can compile palm programs from C or C++ source. You can get it from
http://www.palmos.com/dev/tools/gcc/.
There are IDEs available (such as CodeWarrior for Palm), but none for free yet. However, PalmSource (the makers of PalmOS) have announced that they will release a free IDE (based on Eclipse) for compiling Palm programs at the Developer Conference next week.