Thanks for the info and links. I followed the instructions and the flasher reported that R&D mode was enabled. When I plug in the phone it flashes with a white screen with some blue text on it, and then starts to boot up. I get the dots on the screen for a couple of seconds, and then the screen goes blank and that's it.

I had just reflashed completely yesterday, after having the battery run out on me a week before and not finding any other way to get it to turn on (holding u on the device keyboard while plugging into a computer got me pretty much the same behavior I'm seeing now when I plug in, minus the initial white screen.)

After reflashing it turned on and everything seemed to work fine (with the exception of the power button, which is still unresponsive).

Any ideas on what to try next?