Open Source music software

Can anybody recommend some easy to use (and Vista compatible) open source music sampler/creator software, as there appears to be a lot out there.

audacity is the only one I know of. I didn't think there was that much in OSS world (certainly not winblows compatible)

Audacity is fun to mess with, but I may eventually want something a bit less simplistic in look and feel. Obviously I won't discuss how such software might happen to fall into my hands, but it's gonna be awhile yet anyways.