Cool Little 'Tiling/Mirror/Kaleidoscope' Program
It's only a 30 day free trial, but very fun and the full version is just $12.
Open a photo or clipart in the program then click on the "Silicon Mirror". Move it around to make kaleidoscopic views of your file. Then you can save it or copy/paste into a graphics program and print; or use it as wallpaper.
I know some of the other programs have that option for mirror tiling, but with this you get to move it around almost as if you had a real kaleidoscope.