Steam is making ten games free this weekend as part of its aptly titled Free Weekend promotions. The games include Company of Heroes 2, XCOM: Enemy Unknown and Grid 2. You'll have over 48 hours to play them, as they unlock 6pm GMT on Thursday, October 16. After that you'll need to pay for them, with the promise of substantial discounts.

Here's the list:
Awesomenauts
Blade Symphony
Company of Heroes 2
Don't Starve
Grid 2
Injustice
Killing Floor
Payday 2
Trine 2
XCOM: Enemy Unknown