This is a strange one. Jacob Seidelin has taken Wolfenstein 3D and Flickr, and created a mashup out of them. WolfenFlickr 3D runs in your browser, and allows you to walk around a floor of Wolfenstein 3D looking at images taken from Flickr as art on the walls. You can choose a Flickr search to use for the in-game images, or use a specific user account.

The graphics are understandably low-res, but the concept is very cool. There is no combat in the game - this one's just a proof of concept that allows you to look at a few photos on the walls. You'll notice quite a number of repeat images, or images that failed to load. Obviously this is still a work in progress, but for a few minutes of distraction give it a try.