Portal-themed t-shirt and temporary tattoo by Ian Leno. You can preorder it here, it'll be tomorrow's Tee Fury t-shirt, and Ian's giving away a few tattoos, as described here.
In other Portal news, Kotaku apparently got scammed into promoting a band when the band sent them an email claiming to be part of the Portal ARG. The post originally linked to the band's website and encouraged downloading the band's song at iTunes, but they scrubbed the post to largely eliminate any mention of the scam.
*Portal 2 is $35 at Amazon.