As these things tend to go, it went well for a while, then I started doing real work, then came back to it and got it a little further. Five months later I finally have something ready, and I just posted my first app in the Android marketplace!
It's a dialer app which is supposed to make it much faster to select contacts. It's modeled after the Finger Friendly Friends app for Windows Mobile 6, though I've extended it quite a bit. If you use Android, give it a try and let me know what you think.