Valve collaborating with Adult Swim on something Team Fortress related

Update: It's a hat! Of course it's a hat.

Those who sign up for the Adult Swim newsletter by 4th July will receive a code for a free limited-edition Robot Chicken hat for any class in Team Fortress 2.

The posting urged users to register stating, "this ain't the last you'll hear from Adult Swim and Valve. Stay tuned."

In reply to queries about an Adult Swim Team Fortress cartoon the FAQ curtly replied, "go ask your mother."

Original Story: Valve - developer of Half-Life and Portal - is collaborating with cable network Adult Swim on a mysterious Team Fortress related project to be announced sometime next week.

Unfortunately, the notice on Adult Swim's website is very vague. The full text reads:

"Coming next week Adult Swim & Valve are teaming up for something that you'll probably enjoy. To learn how their video game peanut butter will be getting in our network's chocolate, come back next week. Also: You'll want to sign up for the newsletter. You've been warned."

Below is a twitter window where users are encouraged to tweet #adultswim and #teamfortress with a link http://adultswim.com/teamfortress that sends users to the announcement page.

In addition to numerous mature-themed animated shows, Adult Swim also features several browser games on its website.

Kieron Gillen was particularly smitten by their running game, Robot Unicorn Attack. "It's the best game of its type I've ever played," he said in his 2010 year-end write-up, followed by "It never stops being fun."

It's unknown if the Valve/Adult Swim project is a game or an appearance on a TV show, but with both companies known for high caliber work, the results should be exciting.

We've pressed Valve for comment and will update as we hear more.