I was playing Skyrim, doing the Unfathomable Depths and exploring Avanchnzel. While checking a treasure room, this caught my eye:  If you don't get what's so significant, look here: File:Vent.jpg|Vent.jpg. Would anyone happen to know if this is just coincidence?
Edit: After thinking a bit, I believe it's definitely a reference. During this quest, you see 'ghosts.' It shows events that happened where you explore with the people who were there. This includes the person who gave you the Lexicon, a person who is alive. Sounds familiar? Ghosts work exactly like this in BioShock. Not only that, the halls are patrolled by robots. Now this might sound like a misconception of our Big Daddies, until you realize they all run on soul gems that contain living souls. Beings trapped inside automation forced to guard? Not to mention retro, steampunk style structures in general. A few of the similarities are coincidental, but it seems like they noticed these similarities and put in a solid one or two just for the fun of it.