It's a Valentine's Day gift for family history lovers: Through Feb. 29, ScanMyPhotos.com. is offering free scanning of up to 1,000 4x6-inch photos—all you'll pay is the $19.95 shipping fee (compared to the regular price of $49.95).

What's the catch? The offer is open only to members of several major social networking sites: Facebook, MySpace, Blogger and Flickr (a photo-sharing network). You also have to be a US resident, and the offer's limited to one freebie per person or address. In exchange, ScanMyPhotos.com. asks that you post a review of its service. See the press release for further details.

if you've been thinking about testing the social networking waters but haven't taken the plunge, here's a good incentive.