Are you ready to snap up a ton of PC games to add to your ever-growing backlog? Steam's summer sale has begun, and as always, it offers big discounts -- some bigger than others -- on over 12,000 titles. They include everything from popular franchises, such as Assassin's Creed and GTA, to new virtual reality experiences. And in case you want everyone to know you're a sucker for Steam sales, you'll get a "Summer Picnic Sale" trading card for every $10 you spend that you can display on your profile. The event will go on for 11 days until 1PM Eastern on July 4th. Since Steam won't be holding flash sales or adding any more titles to the list, you can start scouring all the available deals right now.