"Giving a PS3 owner of Portal 2 the ability to also play their game on the PC and Mac is an extension of this philosophy. From our perspective, it's not two copies of a game; it's the same game, but with Sony's help we've worked out a method to allow that Portal 2 PS3 customer to also play their game on the PC and Mac." ...is the right answer. Well done, Valve.

Valve's publications page, with PDFs of papers/talks they've done. Lots of good stuff here.

"This page documents the web API calls that allow you to retrieve information from the item system in Team Fortress 2." Steam now has a Web API. Ooooooooh.

"...the bullets biodegrade when they hit flesh, leaving nothing behind but a blog post." It is a little sad that, as ever, I'm the millionth person to write "I LOVE VALVE" on the internet, but seriously, as I keep saying: I love Valve so much. (I want my white earbuds).

"I see Valve Software today holding the same position in the overall media landscape that Marvel Comics occupied in the early-mid 1960s. In both cases, we have two experienced studios, neither the mainstream-recognized giants of their fields, who made an unusual decision: they chose to spend the creative capital gained from prior commercial success to quietly revolutionize their respective medium's dominant genres, rather than take the safer path of grinding out more derivative sameness."