Seems the build of Android (Google’s Open-Source phone OS) released on the G1 has a nasty, nasty bug. Engadget:
It turns out that G1 firmware revisions RC29 and earlier literally interpret everything you type as command-line operations, so if you happen across a legit command, it’s going to get executed – with superuser permissions, no less. No, seriously. Just go to the messaging app, the browser, or anywhere else a text box is convenient, type “reboot,” press the enter key, and watch magic happen.
I mean, damn.