Here's a roundup of some games that are free to keep and some that are
free-to-play for the weekend (thanks SteamDB).
One of these is a free weekend for DCS: UH-1H Huey
on Steam, so we also should point out that a Sunday will mark the beginning
DCS Fly Everything for Free event (thanks Olaf). This will last for an
entire month so that's your heads up to dig out your joystick if you're
interested. Here's the list of freebies, including some that have already been
mentioned here for completeness: