Tom's Hardware Guide has taken a look at a bunch of small flash cards. This includes Compact Flash, mmC and SD, mmC Mobile and MiniSD, and finally the smallest mmCmicro and MicroSD.
Thinking back a few years, it's not hard to recall the surprised reactions of our parents and grandparents as we proudly extracted CompactFlash cards from early digital cameras. The surprised question, "that's where your pictures live?", sums things up nicely. But when its comes to the latest generation of small memory cards, a granny without glasses probably wouldn't be able to tell one apart from a postage stamp. That's small!