Here's a great optical illusion that you can have a go at yourself. Take one digital camera, a laptop (or monitor, if you're feeling adventurous) and the result? Voila! The transparent desktop! I thought I'd have a try. Here's my attempt..
It's not as easy as it looks, think you can you do better? If so, please leave me a link in the comments, or send your creations here and I'll upload them to the gallery - thanks and good luck!