Lil Guardian Pyro is the winner for the best overall prize at this year's Valve Saxxy annual animated film competition.
Half-Life: Raise the Bar
Half-Life: Raise the Bar is a fan-made short film inspired by the Half-Life franchise.
Portal 2 - Boots
The science of the boots used in Portal 2 is explained in this latest video from Valve.
Portal 2: Lab Rat - Part Two
Read the second part of Portal 2: Lab Rat, the comic released by Valve as a tie-in into the new game in the series.