In the grim darkness of the far future, there are only Warhammer videogames. GOG is getting a head start on all that this weekend, with a big Warhammer Weekend sale and—here's the really good bit—a Warhammer giveaway.
Warhammer 40,000: Rites of War is a 1999 RTS that was pretty good back in the day. PC Gamer US scored it 75%, calling it "an intense, addictive experience," while PC Gamer UK took a slightly dimmer view, criticizing its aging engine and poor AI, and giving it a 65%. (These days, PC Gamer's US and UK offices collaborate on reviews rather than producing separate ones.)
The more relevant number right now, though, is zero, which is the amount of money you'll have to spend to get it. Just go to the GOG front page and click the "get it free" button on the Rites of War banner, and it is yours!
(You can't pick it up from the store page, which I've always thought was a bit of an oddity, but there's a "go to giveaway" button there that will throw you back to the front page, so you'll get there eventually.)
Warhammer 40K: Rites of War will be free on GOG until 6 am PT/9 am ET on July 19, while The Warhammer Weekend sale runs until the same time on July 20.