Using Flickr with Google maps is pretty cool. I found a Mashup that combined photos from Route 66 with a map of the US and the photos placed on the map route showing where they came from. However, I wasn't able to click on the photos to see what they were and they were too small to see a clear image. This would be a cool geography lesson. Maybe students could post photos of places they visited during the summer and it could be posted in a classroom.
Big Deal had links to make the trading cards. Who would want a trading card of a librarian? You could create info trading cards to hand out in your library, though. Like a list of your subscription databases with the passwords to access them.
With Movie Posters, you could have students create posters about their favorite books and post them around the library.