(Useless after July 5th)
Item Details:
http://wiki.teamfortress.com/wiki/Robot_Chicken_Hat
Click Here to Get Your Free Robot Chicken Hat
http://www.adultswim.com/promos/valve/index.html
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https://www.youtube.com/watch?v=drc-LnLKc3A
You won't get this on consoles.
It's a free game, available for Windows, Macs, and Linux
http://gamejam.bossastudios.com/
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https://www.youtube.com/watch?v=K4w5Gd1q490