I wrote a game for Android over the spring/summer this year. I learned java in school and easily found out how to program for Android (I needed to learn the xml on my own). My first app idea was just to make buttons that play drum sounds. After about 3 really big changes to the entire app (I kept learning new things) I considered it complete and was able to enjoy my summer. My proudest moment was fine-tuning the multi-touch, and enabling the same app to work on SDK 2.0+ phones with MT or older phones and not breaking the touch coding. It's been up on the Market for a while, with 25,000 downloads (only 10,000 current installs). But I am starting the new school year and I will surely get back into the app making, either adding new features or a completely new app or game. Here's a screenshot of the game:
You can search the market for "drummer" or "mmk" for MMK Programming. Let me know if you guys like it. I've read a bunch of complaints that the sound messes up on some phones and requires a reboot, so it is unplayable hence the small percentage of active installs, but it works fine on all the Droid's I've tested, hence all the positive reviews.