Do you like the game Portal? Then you’ll probably want to buy the eBook.
The Final Hours of Portal 2, a new enhanced eBook app, was uploaded to iTunes yesterday. I bought it, and I heartily recommend that you do so. It has all sorts of interesting details like video clips, a 3D model of the co-op robots, a deeper explanation of the viral marketing campaign Valve ran back in March 2010, and several panorama photos of Valve offices.
I’ve only played with it for 10 or 15 minutes, but I already know that I am going to deeply enjoy reading it. It was worth $1.99.
Update: this eBook was released in partnership with Valve, not by Valve itself.