Two examples are Gboid and Jarcade. When playing either after a few minutes, display goes blank and Droid does a hard reboot. It has happened twice with each emulator.
Played the heck out of these and other emulators and have NEVER had this happen with the G1.
Actually, the G1 never did this with any app and have had the G1 over one year. Not a good sign for a device I have had one week.