Clay Aiken (search) lurked outside a house, Emmylou Harris (search) stopped by a university, Nick Lachey (search) dropped in on a stranger's workplace and Moby (search) played with dogs while making special deliveries in honor of online retailer Amazon.com's 10th anniversary.

Over 10 days, 23 Amazon customers received a surprise visit from a celebrity associated with their order.

"American Idol" runner-up Aiken dropped off his memoir, "Learning to Sing." Lachey delivered all three seasons of MTV's "Newlyweds: Nick & Jessica" (search) on DVD, while musicians Moby and Harris showed up with their CDs.

The moments were captured on tape and the videos are available to view on Amazon.com.

Other celebrities who participated in the surprises included Harrison Ford, Don Cheadle, Jeff Bridges, Minnie Driver, Fat Joe and Michael J. Fox.

Says Aiken on his video clip: "It's very rare that you get to go up and meet fans and especially at their house and surprise them. To come and knock on somebody's door is kind of a neat experience."