My all-time favorite musician is probably Björk, followed by Beck and Trent Reznor.
There are a ton of musicians/bands that I love, but if for some hypothetical reason I had to limit myself to my top three, it would be them. I've been listening to Björk since I was 8, so she's been important for me for a long time, but I didn't get into Beck until college, and only discovered Trent/NIN last year!
I'm listening to NIN right now, and it always makes me feel so cozy and content, which makes me laugh because of how drama-llama emotional it is.