For me it's all server room gear on UPS. Backup devices also, mainly because they don't like the surges and spikes that accompany power outages/restores. I'd sooner use some of the UPS capacity than have to replace the tape drive.
PCs normally don't get a UPS. It's just not cost effective where I am because even a very small UPS will cost $150+. As all work files should reside on the servers, not the local drive, there will be minimal loss when the power goes out. Anyone working on their local drive is more likely to get a lecture than sympathy from me. One exception I would make the this is for people such as programmers, who may be running very time consuming processes (e.g. compiling large programs) on their workstations. Personally, if I do any programming or other work locally I use my laptop.
I also keep a rechargeable torch (flashlight) in the server room, which has no lights during power outages. It just means that I don't have to stumble in the dark and not have to worry about the batteries being flat just when I need them.