1.) this is an insanely geeky thread...LOVE IT
2.) I have 2 graphing calculators that I use, my old reliable and totally awesome (though it doesn't have an apps functionality) Ti-83 (notice the lack of the Plus) it uses less power than most graphing calculators so in my 4 years of using it nearly every day, i replaced the batteries once, and with a lack of games, i find myself slightly more focused at times, or at least programing functions instead of gaming.
Now for the Flagship Calculator, this thing is the supreme commander of all calculators (and i think it has that function buried deep deep into it (i've yet to find it)) The
HP49g+, yes that. Well though it technically is owned by my dad i'm borrowing it until he asks for it back, this thing has EVERYTHING (including the Coffee Maker program that some guy wrote for it on the net) it's crazy, its fun to use and totally not legal to use on the SAT...though it'd be fun to do that. He found a great deal on ebay for it a little while back, he paid about 20 bucks for a 175 dollar calculator, gotta love ebay.