Remember back when Half-Life 2 launched and everyone was forced onto Steam? Remember how many people hated it? That seems like a lifetime ago, and now most people would not be able to imagine PC gaming without Valve’s digital shopfront.

In keeping with bank-balance-destroying tradition, Steam has launched a Christmas sale. Practically every single game on Steam is currently being discounted by a bajillion percent, so if there’s anything you missed during the year, then now is a good time to pick it up.

But sales on Steam are like hookers in Greenpoint – there’s no lack of them. The really cool news is that there’s a big pile of virtual presents sitting under a virtual tree. The Great Gift Pile wants you to dive into it, but you’re going to have to work for your presents.

Starting from now and running until 01 January 2012, Steam will be giving you a list of objectives to complete in various games. If you complete an objective (similar in requirement to Achievements) then you get a present from The Great Gift Pile! Hooray! It’s easy! Of course, you have to own the games that have objectives for the day, but if you do then you’re in luck.

The presents can be one of two things: either a gift like a free game or a coupon for future discounts, or you might get a lump of coal. Save enough lumps of coal and you can trade them for a present instead. You might, however, save all your lumps of coal because each counts as an entry into the Steam Christmas competition.

The Christmas competition is a giveaway in which you could win Valve game packs or titles off your wishlist (see, that’s why you needed to compile a wishlist on Steam recently). There is one Grand Prize however, the recipient of which will win EVERY SINGLE GAME ON STEAM. Yes, ALL OF THEM.

You can only enter if you have at least ten titles in your wishlist, so start compiling that list if you haven’t already. Then head over to The Great Gift Pile section on Steam and start playing the games required to complete the day’s objectives.

Maybe also apologise to friends and family for your conspicuous absence between now and next year.