I think there may have been pebcar before - if you hold done home + volume while inserting the SD card with an autorun.xml in the proper place it will load into test mode.
http://twitgoo.com/3bry1
I also learned that if you insert an SD Card that has ext2 partitions on it (I use the card for other things) in addition to a FAT-32 partition, the phone will just keep rebooting itself.