Image Capture Extension eating up CPU cycles

On my MacBook Pro running 10.6.4, anytime I plug in a camera-type device--iPhone, iPad, my digital camera's SD card--the Image Capture Extension immediately jumps to the top of the Activity monitor, using up 100% of CPU cycles and the Real and Virtual memory use continues to climb non-stop (I've watched it climb to over 9GB of virtual memory so far). After a few minutes, the computer is completely unusable with the spinning beach ball appearing constantly. In the meantime, the devices I plug in do not show up in iPhoto or the Image Capture app. The iPhone and iPad will show up in iTunes (eventually), so it's definitely related to the photos side of things, I think.

Also, the problem does not appear when I boot up in another account so it's also definitely related to something in my main account. I've tried reinstalling from the combo updater, which didn't work. And I tried trashing the Image Capture prefs and removing login items, which also did nothing.

Took it to the Genius Bar yesterday and they were stumped as well. A full wipe and reinstall of the system is not an option at this point as I'm on an extended work trip and have no Snow Leopard disc. Anyone have any suggestions? Thanks much!