Tried uninstalling G-Alarm, It still does it, I've never set an alarm for 23:59 and as far as i know that's the only time it wakes up.
Methinks a hard reset is coming
Do you have the phone radio/GPRS connection turned off at night? It may be that QuickGPS is trying to download fresh data at midnight, but failing if there is no data connection. Try going into QuickGPS and disabling the auto download, and auto-notification options.
In fact, all WM and PPC devices do 'wake' to a suspend state every day at midnight, when the clocks/alarms/timers are resynced, but usually the screen remains off while this happens.
Another alternative may be to download a trial version of SKKV S K Tools, and check the Notification Queue for rogue entries. With the trial version you can only remove 6 items at a time, but you can do this if necessary, then close/reopen the program and do another 6.