Half-Life fan remake Black Mesa is among the first ten games to be accepted by Valve on its new community rating portal, Steam Greenlight.
Undead sandbox survival title Project Zomboid and point-and-click puzzler McPixel were also accepted.
Also on the list: horrifying Half-Life mod Cry of Fear, beautiful exploration game Dream, free-to-play online shooter Heroes & Generals, feudal RPG Kenshi, Half-Life 2 zombie mod No More Room in Hell, sci-fi survival horror Routine and city-building RPG mash-up Towns.
"The Steam community rallied around these titles and made them the clear choice for the first set of titles to launch out of Greenlight," Valve business developer Anna Sweet explained via the company's blog. "Since launch, hundreds of titles have been submitted, with more coming in every day. We expect to be announcing more titles coming to Steam via Greenlight soon."
Valve's first crop of successful Greenlight games marks an important next step for the service, following a somewhat bumpy launch.
An initial lack of verification controls led to the service being flooded by fake games and copyright-infringing submissions and other nonsense. Valve was forced to ban Steam users creating the false game entries and begin charging a $100 entry fee to the service, a sum it will donate to the Child's Play charity.
Successful Steam Greenlight games will begin appearing on the service shortly.
"Valve has been in touch to say that, through the power of community voting, we've been allowed a place on Steam!" read a statement on Project Zomboid's Greenlight page. "It's a massive day for us, and we'd like to take the opportunity to thank each and every person who clicked the Greenlight page on our behalf. It really does mean the world to us.
"It won't be an overnight process getting PZ onto Steam, far from it, but thanks to our community and the good people of Steam we've vaulted over one of the most challenging hurdles."
Pat on the back, everyone.