As the title sales, Steam is having a holiday sale with thousands of games being discounted, and special daily deals with extra discounts. Portal, Fallout games, Battlefield Bad Company … just a few of the heavily discounted titles available right now.

So what are you waiting for? Get your games from Steam

Following the success of the first Humble Indie Bundle, the same deal is back, with five games being offered for the price of … whatever you’d like to pay.

Normally retailing for $85, these five indie games can be had for as little as nothing (boo!) or as much as you want, and you can even decide how your money will be sent – on the game, or to charity. The average payment so far is around $7, and the top contributor paid $2000 for the pleasure.

The games are Braid, Cortex Command, Machinarium, Osmos and Revenge of the Titans. And of course, the games are all DRM free.

So get your humble indie bundle today here

Update: Bonus for users donating more than $7.50 – you get the first Indie Bundle (another 5 excellent games) for free!

Alien Swarm is now a full, Source-powered 4-player co-op game (originally a UT 2004 mod), and it will be given away free on Steam on Monday (US time). All you need to do is to download the Steam software and then come back on Monday 20th July at 12pm (US PST) to get the game by going to this page.

That’s right, it’s not a typo. Save $479 (that’s four hundred and seventy nine dollars) on Steam’s Sega Complete Pack, featuring all of Sega’s best hits on Steam, including Aliens vs Predator, Empire: Total War, Football Manager 2010, Medieval II: Total War, Napoleon: Total War, Outrun 2006, Rome: Total War, SEGA Rally, Space Siege, Virtua Tennis and more, plus lots of add-on packs for all of these games. The total of the normal individual purchase prices of all of these games is $569.28, but you can get it all for only $89.99 for this week.

Get the Sega Complete Pack

The award winning Portal game is now free on Steam until the 24th of May. All you need is the free Steam application and then you’ll be able to download and install the game at absolutely no cost.

Download Portal for free here

To raise money for charity, and also raise awareness of the important issues for the game industry, such as piracy and DRM, independent game developers have joined forces to offer a collection of 5 hit Indie games, and you get to choose how much you want to pay!

You can also choose to donate part of all of your purchase price to the EFF, fighting for your online freedoms, or Child’s Play, which donates toys to sick kids in major hospitals around the world.

The games in the bundle are: World of Goo, Gish, Lugaru HD, Aquaria and Penumbra Overture

Buy the Humble Indie Bundle here

To celebrate the launch of Civilization V soon, Steam is offering 75% off Civilization IV: The Complete Edition which features the award winning original Civilization IV, plus the Warlords and Beyond the Sword add-on packs, plus the new updated Colonization. Normally, this pack retails for $39.99, but you can get it this weekend for only $10. Or you can buy each individual title at 75% off.

Access the Civilization IV sales now

Steam is having a Codemasters racing games sale, with 5 games, including DiRT 2, reduced by 75%, with games as low as $2.50 (ToCA Racing Driver 3). Or if you buy all 5, then you can save a further $7.46 on the entire package, getting 5 racing games for $17.50.

Access the Codemasters racing games sale here

Major game companies don’t hesitate to charge an arm and a leg for new releases, with most launching around $60 these days. You may not be aware but there is quite a few older commercial titles freely available, just waiting to be downloaded. Dozens of old school favorites like Doom, GTA, Command & Conquer, Fallout, etc. can be had totally free.

Here is a few of the most popular games:

• Command & Conquer: Tiberian Dawn, Red Alert, Tiberian Sun
• Doom
• Fallout
• GTA & GTA 2
• The Elder Scrolls: Arena, Daggerfall
• F.E.A.R. Combat

See the whole list here.

Microsoft is bringing you even more discounted PC games, one per week, with up to 75% off selected games. These are downloadable games, and you’ll need the Games for Windows Live client.

From 2 April to 5 April: Red Faction: Guerrilla for $9.99 (50% Off) – Expired

From 6 April to 12 April: Battlestations: Pacific for $17.49 (50% Off) – Expired

From 13 April to 19 April: Grand Theft Auto IV for $14.99 (50% Off) – Expired

From 23 April to 26 April: Resident Evil 5 for $24.99 (50% Off) – Expired

Access the sales page here