I know Zwift is more than a game, BUT…
How about Zwift in Space? We could have a mobius strip velodrome, a gravity assist hillclimb, and all sorts of things that are impossible, even in Watopia.
Click For 45 sec Video
Sorry about the production quality, and the botched soundtrack.
Kinda reminds me of the Highline, but I love the idea of the moon (or Saturn/Mars/Jupiter) It would need features to keep the background interesting. Giant spaceship like in Alien films? Where are Watopia aliens from anyway?
Also, perhaps, in Zero G, the course could knot back on itself, upside down or even orthogonal to itself. The TorusGeometry class in WebGL is particularly interesting to ride around.
The aliens live in the desert, somewhere. I haven’t been abducted yet, although I’m still trying.