In our last issue, we wrote about the portable NeatReceipts scanner, which weighs less than one pound and can even scan legal documents. Now, there's a new entrant into the portable scanner category: the Mobile Office D600 from Plustek. The big advantage: it can scan both sides of the page at once, at 3 seconds per page. That makes it a good tool for business travelers who need to scan business cards, checks, receipts or identification cards on the road.

But it has some drawbacks. It can only scan documents up to 5.8 inches by 4.1 inches, and it costs $329, compared with $199 for NeatReceipts. (At Buy.com, you can find the D600 for $297 and NeatReceipts for $76.99.) Our advice: only buy the D600 if you really need the double-sided scanning feature.