One of the CDs I got for Christmas is Depeche Mode's "Sounds of the Universe." I think it's fantastic ... they really got creative with all of the old synth technology that they utilized for that album.
I focus a lot on them and U2, Pink Floyd, Rush, INXS, and some other bands. I like some solo artists like Sheryl Crow.
Some of the less mainstream stuff that I've been getting into lately include Bliss and Zero 7. I also like jazzier stuff by the likes of Richard Elliot, Spyro Gyra, and Galactic. I'm even a fairly big fan of Enya, and I'll even venture into classical every now and then.
Pandora is a site I use a lot when I'm working on my PC.
I also write my own music.