Rasterbating is Cool
This is a very, very cool resource. It takes any jpeg image from either your computer or the web and allows you to stretch the image out to a very large size via several sheets of paper.
From the site:
The Rasterbator is a web service which creates huge rasterized pictures out of relatively small image files. The pictures can be assembled into extremely cool looking posters up to 20 meters in size!Click here to see some examples.