Update 5/3/2011: The Deal on Xbox 360 is over, but the PC version is still at $29.99; also, the PS3 version is now available and it’s on sale for $34.99 [that’s 42% off the list price of $59.99]. I’m not sure how long these will be discounted, so grab it now if you want it.

The video game deal of the day over at Amazon today is Portal 2 for Xbox 360 and PC.

– Xbox 360: $34.99 [42% off the list price of $59.99]
– PC: $29.99 [40% off the list price of $49.99]

Note, this deal is only for today, Sunday, May 1, 2011, til midnight PST while supplies last.

Portal is an incredibly popular game with a very faithful following. The tricky puzzle game with a subtle backstory and super-popular, deceptive villain sucks you in from the start and before you know it, it’s all over.

With a game like that, as you might imagine, a sequel has been demanded for a while. And with the game running fairly short and with three years now separating us from the original, you might also imagine that the fans’ demand has been something along the lines of “Where in the hell is our Portal 2 already!?!?”

Well, Valve has an answer to just such a question at E3 2010, and you can see what they brought with them by clicking over to the other side right now.