Steam are having a Valentine's sale later today, and for once we know about it in advance. You'll find the list of discounted games here (opens in new tab), although the discounts themselves haven't been detailed yet. Still, it should give you a bit of time to safely lock away your wallet, delete your saved bank details, and throw your computer into the sea—alternatively, you could pick up some lovely games for not much money.
This sale's all about Valentine's day, which is either a sickeningly commercial fake celebration of love, or an excuse to go out for a meal, depending on whether you're in a relationship or not. Maybe this year, Steam says, you could get your loved one what they really want: a cheap co-op game or two. This weekend sale is dedicated to games featuring co-operative multiplayer, including the Borderlandses, the Saints Rows, Towerfall, some Sanctums, Don't Starve Together and Magicka.
It's a pretty good list, even if I can think of loads of great co-op games not featured. Maybe more will be added when the sale goes live at 10am PST/6pm GMT today?