Portal 2: Pretty Much Every PS3 Question Answered (and that Cake thing, too) – PlayStation.Blog
Portal 2 to be cross-platform, PS3, PC and Mac | TweakTown
Buy Portal 2 PS3, get PC/Mac version free & Steam support – Destructoid
Portal 2 on PS3 was the only Valve game on console to be cross play and cross progressions with PC via logging into steam on your PS3 and you'd get steam achievements +
Dragon's Crown - Wikipedia
Portal 2 will let PC and PS3 gamers play together | PC Gamer