<< I'm not sure if this is a fluke, but it's really sucking down my battery.  Playing a movie for 15 minutes just sucked away 1/3 of the battery life. >>
 And thus you have discovered the biggest problem with MicroDrives... they are not solid state and therefore use up a ton of power. A MD is just a micro hard disk drive, with the same innards. They suck power like crazy.
You would be best off just waiting for 1GB CF cards (won't be long now), or get a PC Card sled and CF-> PC Card adapter for your IPAQ (making it a huge brick in the process) because they have a built-in battery to power the PC Cards.
l2c