You've seen GTA 5 with Oculus Rift, Now see GTA 5 with the Virtuix Omni.
GTA 5 PC has unlocked a number of exciting possibilities.
Modders and hackers are still working on making the game's files accessible to third-party creation tools, but several cool things have been produced even with this barrier still in place.
For example, here's a gentleman playing GTA 5 using the Virtuix Omni treadmill.
I can easily think of a dozen reasons not to run while gaming, but if that's your bag, this is pretty cool. When I see set ups like this, in a world as detailed and infinitely explorable as GTA 5's, it really makes me excited about the future of VR. Maybe just via direct neural implants, though; running is hard work.