Steam is discounting the highly rated PC game Mass Effect by 50%, to only $9.99, for this weekend only. With a rating of 89 on Metacritic, it’s a fantastic game at a fantastic price.

Buy Mass Effect

Steam’s weekend deal for this week is a massive 66% Off their entire range of Half-Life games, including Half-Life 2 and all the episodes. You can buy the games individually, or buy all 8 titles for under $17 in the Half-Life pack.

If you’re an even bigger fan of Valve, then you can buy the complete Valve pack featuring every game the company has produced, and you’ll get 10% off the normal price during this weekend as well.

Shop the Steam Half-Life/Valve Sale

Steam’s latest weekend deal gives you 10 indie games for $29.99. The pack includes World of Goo, Braid, Audiosurf, Crayon Physics and other popular indie titles. It’s a 75% off the normal price.

There is also a 5 game pack, at 66% off. The offer will end on midnight Sunday as usual for weekend specials.

Access Steam’s Indie Game Special

Steam’s weekend deal is a big one, by offering 50% off all Relic games which includes Company of Heroes and Warhammer 40K games.

Of particularly good value is the Relic Super Pack, which contains Company of Heroes, CoH: Opposing Fronts, Warhammer 40K: Dawn of War and Dawn of War: Dark Crusade, all four games (or two full games plus two add-ons) for only $24.99. Alernatively, you can also get these separately (Company of Heroes for $7.49 is great value).

Check out the full list of discounted games here

Steam’s weekend deal this week is for the game Brother In Arms. But you don’t just get one deal, it’s actually 3 (or 4) deals. Buy any of the Brother In Arms games (Road to Hill 30, Hell’s Highway and Earned in Blood) and you get 50% off each game (from only $4.99). But if you decide to buy all three games, then you get a massive 60% off, or $19.99 for three full games.

Buy Brother In Arms for 50/60% off

Steam’s weekly special this week is the highly rated racing game, GRID, which has been discounted by 50% to $14.99.

Click here to buy GRID for 50% Off

For some reason, Steam has a bunch of deals going on this week and weekend (all are week long deals, unless otherwise indicated):

Assassin’s Creed – $9.99

Splinter Cell – $4.99

Splinter Cell: Double Agent – $4.99

There are more deals on the steam website, so go there and have a look.

Steam’s weekly special this week is the highly rated Call of Duty: World at War, which has been discounted by 50% to $24.99.

This game was voted the best game of 2008 by our visitors, and one of the best selling games of 2008.

Click here to buy Call of Duty: World at War for 50% Off.