I use an Epson PhotoPC 650. It was cheap, about $250. That was the primary criteria. I also chose it because 1) it uses AA batteries, not proprietary rechargeables, and 2) it uses a CompactFlash card, which requires less battery power than spinning a floppy like the Sonys (did).

I wish it had a zoom.

There're a bunch of pictures taken with this camera at http://albums.photopoint.com/j/AlbumList?u=608197.