Zeno Crivelli just emailed me with a new app he just finished working on at the Swiss Federal Institute of Technology. It's called MathME and basically brings the power of a graphing calculator to your J2ME enabled phone. I get lots of emails with links to new projects, but this is definitely one of the coolest ones in a while.
And honestly, I'm not a math guy (as you probably know by now). I have no idea what's going on in the pictures in the tour section. However, this is one of those apps which shows the real power of the mobile phone and something I just never thought of doing. I'm sure someone out there right now is thinking "Wow! Cool!" and grokking the fact that their mobile phone is actually a powerful little computer in their pocket for the first time. I'm not sure how this compares to a TI calculator or other math apps for PDAs, but it looks pretty impressive.
The app works on mobile phones, but watching the video of Zeno write formulas using a pen on a PocketPC is almost as cool as the app itself... ;-)
Update: I just got the fact that this thing is a client/server app which talks to a Mathmatica instance on a server. Not as cool as the whole thing running on your phone, but still a pretty interesting app! In fact, it's probably a lot more powerful this way.