I use several Java-executable apps on my USB thumb-drive. These should not require additional development (but this seemed the best forum anyway
PLCash.jar - a personal finance program
JTides.jar - a tides calculator
SatFinder.jar - a satellite finder (for television, hams, etc)
All the above can be found at http://www.arachnoid.com. Be sure to read the developer's statement about what he calls "CareWare".
I am a big fan of Java-executable apps due to their platform-independent nature. If anyone has other Java-executable apps, please post them here.