I was checking out Akiba PC Hotline
http://www.watch.impress.co.jp/akiba/
and I stumbled across this:
http://www.xonixwatch.com/en/product...stratedId=F014

It's bootable and has a capacity up to 512 MB. I immediately thought of Knoppix. MorphixCombined-HeavyGUI would fit perfectly with enough room for a boot sector and a few documents like your address book and so on.

-edit:
A couple of typos fixed.