Though my first attempt using the TI-83 was very successful, actually trying to program or debug what you've written is difficult. To be honest, you can only expect so much from a limited calculator interface. So those of you who wish to try, be forewarned its not as easy as it looks. You will undoubtably have to commit some time to learn and understand it.
Word of advice, if you make a mistake (any mistake) press CLEAR and ENTER to wipe out that line, and start over.
But hey, when it works, it works just great!