Sometimes my Android (HTC Inspire, OS: 2.3.3) would lock up hardcore. Nothing I could do would restart it, short of letting the battery drain all the way down (My phone doesn't even give me access to the battery, so I can't take it out and put it back in).
I finally found a trick that will do it, but it has these prerequisites:
- Another machine (Windows, OSX, or Linux)
- The Android SDK - http://developer.android.com/sdk. The download is ~30Mb, and once you download it you will have to extract it somewhere where you can later find it. Linux users can open a terminal and run tar xvzf android-sdk_r*-linux.tgz
- On the phone, enable Menu > Settings > Applications > Development > USB debugging. As far as I can tell, there is no harm in this being always on. If you don't have it set in advance, though, this trick will not work.
Now, the next time you get a crash...
- Start up a terminal (Windows users can do Windows+r,"cmd",Enter -- other OS users already know what to do. =) )
- cd wherever/you/put/the/sdk/platform-tools (Or add it to your $PATH/%PATH%)
- Run the command. On Windows it will be: adb shell reboot Elsewhere it will be: ./adb shell reboot
- Enjoy!