Yeah I'm pleased to say that it looks like you can boot from the Sandisk Expresscard adapter. I restored my DiskWarrior DVD image to my SanDisk Extreme III SDHC 4GB card and it booted fine and it was significantly faster booting than my DVD. If only I could easily put both DiskWarrior and DiskUtility on my SD I'd be happy. But I think you need a 16 GB drive in order to restore your OSX image onto. I guess that will be SL when it's released.