Valve are showing us the love by launching a new co-op sale on Steam for Valentine's day, where the focus is going to be on a selection of multiplayer-centric games. Titles such as Saints Row IV, Portal 2 and Borderlands: The Pre-Sequel are all discounted. The sale is kicking off later today at 6pm GMT / 7pm CET, but you can still head this way to see which games are going to be included in the promotion.