http://www.grand-illusions.com/opticalillusions/dragon_illusion/
When someone wants their mind blown, I send them this link. You can download a printable PDF and watch the video on how this illusion works - it's not that tough, print 3 copies just in case :P
Autonomous quadrocopter flies through windows, straight into our hearts video -- Engadget.
I'll take one, (PRETTY)PLEASE!
... or (almost) clever video editing, ha!
This was a viral video made for Dakine backpacks.