More than one thousand online photo-printing services have entered the marketplace in the history of the Web. Only a few remain. The most successful survivor is Shutterfly, founded in 1999. The 16 billion pictures currently sitting on Shutterfly’s servers aren’t your garden-variety snapshots of sandwiches and shoes. The pictures on Shutterfly are treasured images, and destined to decorate photobooks, prints, calendars, wall decals, mugs, greeting cards, and other items.