(website with clear step-by-step instructions to teach students how to program for TI-84 and TI-Nspire)
Add files to several 84's at once, PC and Mac - FREE!
(includes TI-84 greyscale emulator, too)

Activity that integrates Algebra, Geometry, and Cryptology.
Works on both the TI-84CE and TI-Nspire platforms
I will email you when these files are available! (by Nov 29)