Psi-Ops for Free
The psionic action game Psi-Ops: The Mindgate Conspiracy is now being offered for free by FilePlanet. Of course, you will have to put up with ads, but a version of the game without ads is still available for purchase.
The game was originally released back in 2004 to generally positive reviews. It had players controlling a soldier with psionic powers going up against an agency of similarly psi-powered evildoers.