beFunky - This is by far my favorite tool. With beFunky you can take any of your photos and turn it into a cartoon like drawing. You can either convert it into a black and white sketch drawing or into a colorful animated painting.
This tool lets you take any image and convert it into a huge (up to 20 meters), awesome looking, rasterized wall poster.
MagMyPic - Fun website where you can turn pics into cool magazine covers.
Graphita - Graphita is a quick online app that lets you add some fun to pics by using captions, funny objects, speech bubbles, notes, doodles and more.