I had one of these things a couple of years ago, it was 3"x3"x.5" think and the LCD couldn't review images but it did have 20gb. I got it for less than $100 and it worked great until I really needed it. Saturday night after a race in a hotel room and I couldn't get it to charge, and the battery was dead. I guess when I plugged it in the night before it didn't charge either.
So I was up early on Sunday morning waiting in the Frys parking lot looking at my options. More CF cards, Epson media device, or a 15" Compaq refurbished laptop for $400. With 60gb HD, 1gb of ram, 1.5ghz it's nothing special but worked great. I found a Kinkos and plugged it in and started coping and made it back to the track before the start of the first race.
I still have and use the laptop all the time even for my other business, I threw in another GB of ram and it enough to copy, review, & post photos and I can even use AutoCAD.