The stuff I like isn't really on youtube in any official form, so rather than posting a bunch of crappy user vids that use the songs, I'll just link to Grooveshark (which is better than youtube anyway ). Just click the link and it'll play.
I split my music up by mood, more or less. When I need to stay awake or in the mood for something upbeat, I've been listening to a lot of new age stuff.. Delerium and Sleepthief are good examples:
Delerium - After All
Delerium - Truly
Sleepthief - The Metro
Sleepthief - Just Say It
Then there's when I'm in the mood for something a bit calming and I happen to *love* piano, so I like Vienna Teng. Her first CD anyway.
Vienna Teng - Eric's Song
Vienna Teng - Say Uncle
Then there's some stuff sort of inbetween. I like Jem, she's sort of pop but it's not the standard US flavor (she's European) so it's actually good.
Jem - 24
I should probably stop here for now