A list of Oculus Rift DK2 games and experiences is maintained, along with download links, at: http://www.theriftarcade.com/oculus-rift-dk2-supported-games/
As tests of the Oculus DK2 there are some excellent 3D immersive environments to try…
Undersea with Ocean Rift
http://llyrie.blogspot.co.uk/2014/07/ocean-rift-demo-for-dk2.html
Image from Llyr’s VR Experiments – http://llyrie.blogspot.co.uk/
In Flight with Combat Flight Simulator
https://www.digitalcombatsimulator.com/
Not yet functioning in Direct Rift Mode.
In Space with Solar System Explorer/Discovering Space and Titans of Space
https://developer.oculusvr.com/forums/viewtopic.php?f=28&t=10869
Solar System Explorer had a name change to Discovering > Space… and a limited travel version was made available for demonstrations which allowed travel out to Mars… ahead of a paid release which will allow for further exploration…
Titans of Space – another good tour of the solar system and other stars (some enormous) in our galaxy…
Manoeuvre in your spacesuit around a high resolution model of the International Space Station (ISS) over Earth with high resolution NASA textures in VRSpacewalk.
You can experience a very busy Moonbase in a Gerry Anderson’s Space:1999 experience by Liam Goodison at https://share.oculusvr.com/app/space-1999-demo