Android modders beware: Droid X bricks itself if you try to modify it
So, what kind of modding triggers the eFuse? Messing with the bootloader itself, the firmware, or the Android kernel will all result in bricking. There's no way to delete the software, either, as it's apparently part of a chip that the Droid X needs to boot, and eFuse lets the chip reprogram itself (in this case, to stop your phone from booting). You can get more details from a post on the MyDroidWorld forums. What is going on, here? It doesn't make any sense that companies marketing an open phone would want to treat their customers this way.
Update: Boy Genius Report says the bootloader is probably the same as the one on the Milestone, and that it "may not" or "probably won't" brick your phone. They do suspect, however, that it will be "difficult to crack."