Recs for MUSIC only discs for my 5.1 surround sys

Just wondering of any of you guys have specific recommendations for discs to listen to on my 5.1 surround sytem. I have a Blu-ray player that also plays CD'S. I've listened to movies obviously and they sound great, but I was wondering if any jewels exist out there where I could just listen and take advantage of the 5.1 system instead of just plain stereo. Any genre of music (other than country) is fine with me. Suggestions? (I know the purists like to listen to just standard stereo)