LINKS in no particular order.
(oh, and I won't link to community or public-site blog pages like myspace or blogspot)

related:
reUniverse.org
OverClocked ReMix
Subco Netlabel
Remix:ThaSauce
Sound Alliance

great labels:
Protagonist Records
Kosmic (Archive)
Pause Music
Ektoplazm (Portal)
8-Bit Peoples
Kahvi Collective

community:
Scene.org
The ModArchive

software:
Schism Tracker
Reason

buddy: (music)
Stefan Strand (Between Interval/Sublunar/Monodrive)
Andrew Aversa (zircon)
Martin Binfield (Binster)
Heath Morris (Siamey)
Danny Adler (SGX)
Scott Porter (OverCoat)