My latest project, which as usual has started out in a flurry of exceitement but will soon fizzle out as the real world of programming problems set in, is a 3D adventure in the style of Deus Ex. Here's a screenshot of the setup. There's no game, just an environment to walk around in:
So far I've got sliding doors, some stairs, and a man with a pidgeon chest, so there's plenty of stuff to do, like a story and pretty much everything.
BTW, this is written in Java using the excellent jMonkeyEngine.