If you fancy wandering around the spooky ruins of BioShock's Rapture in VR and shooting headcrabs, boy have I got the mod for you.
Return to Rapture (opens in new tab) (cheers, UploadVR (opens in new tab)) is a Half-Life: Alyx mod created by wim.buytaert.1988 that smooshes the two universes together. The Combine has discovered the location of Andrew Ryan's underwater city and want to get their alien hands on his fancy Plasmid tech. As Alyx, you'll need to stop them by getting it first.
You won't be able to use Plasmids, but at least you've still got Alyx's handy gravity gloves. There are still plenty of nods to BioShock, though, including working Vita Chambers, audio diaries and vending machines. The latter let you recycle junk you find lying around, turning them into useful items.
It uses a mix of Half-Life: Alyx assets and new ones to create something that, while not perfect, certainly evokes Irrational Games' dilapidated dystopia. The only thing that's really off are the signs, some of which are just plain text pasted onto vending machines and Vita Chambers.
If you, like me, can't wear a headset for very long without feeling a bit iffy, you'll have an easy time of it in Return to Rapture. It should only take 25 minutes to finish up, so it's a whirlwind tour rather than an extended stay. Judging by the state of the city, that's probably for the best.