Some great and inspired choices on this thread. I might also add the following, which have given me a lot of pleasure over the years:
Frumpy - Live
Achim Reichel - Erholung
H.P. Lovecraft - May 11, 1968
Fields of the Nephilim - Earth Inferno
Miles Davis - Agartha
and, warts and all, Led Zep's Song Remains The Same