Moke - Carnival
This short-lived British band opened for King's X a while back, and they were really great. Lots of fun, great vocalist, and cool songwriting. Carnival is the second of their only two albums. Damn, I wish these guys would come back. I'll try to update this thread later with youtube clips to share.
Spock's Beard - Snow
Spock's Beard is well-known to neo-prog fans, but how many people fit that description? Anyway, Snow was their attempt at a rock opera concept thing, and I really, really dug it. Pieces of it are reminiscent of Tommy, Lamb Lies Down on Broadway, and Fragile (because they have a very Yes-ish sound going on) but I just love the record. Bug fan of the band, even though they're on singer #3 now.
Galactic Cowboys - The Horse that Bud Bought
These guys were always closely associated with King's X, but they were always a very different band. They were around for a while and released quite a few albums (all of which are good, IMO), but they were especially hard to find at record shops before you could order everything off Amazon. Even in early days of Amazon, I had trouble finding their albums. Anyway, The Horse that Bud Bought represents all aspects of their sound in the best way, I think. Heavy, aggressive, melodic, and silly all at once. I love it.
I would be tempted to put stuff from Porcupine Tree on here, but they are getting pretty well known. Same goes for many of my other favorites like The Decemberists, etc.
What albums do you love that we've never heard of?