One thing never changes, and that is that everything changes. Welcome to Between, a multiversal nexus of comic book worlds, a space terminal where all worlds meet. Space and time fight for the remote in this massive complex travel is the name of the game, but businesses have sprung up amongst its vaunted halls, and there are all manner of services available to the lost and weary who find themselves here. While there are many permanent establishments which seem to be able to find a location and stick to it, there are just as many floating locations vulnerable to the swirls and eddies of time-space fluctuation. Maps are constantly being rewritten, and are easily accessible via hand-held communicators freely available everywhere.
Want to play a scene set in the DC or Marvel universe? Do so. What about a scene set in the terminal itself? Go for it (and check out already existent settings for suggestions!). How about a different comic book universe or an entirely new universe altogether? You can do that. In the depths of space? Under the ocean? Back in time? It's all possible. What about a casual network-style post? That's what the communicators are for.
If you can imagine it in an airport terminal or mall, it's probably here, plus more.