Hi,
Musician -- Peter Hammill and his band Van Der Graaf Generator
Band -- Amon Duul 2 as no band has a more impressive catalog, from Plallus Dei, to Yeti, to Carnical in Babylon, to Wolf City (one of the best albums ever for me!), to Vive La Trance.
Band2 -- Djam Karet as one of the most impressive American band, with unbelievable material all along, and 25 years later they can still do "The Trip", and blow you away for some 40+ minutes, and no drums for the first third of the piece. It takes some kind of patience, care, and beauty to do that.
Musician2 -- Frank Zappa, even though many may not enjoy or appreciate his work, because of this or that, by the time you hear "200 Motels - The Suites", you realize that you have something here that is above and beyond any ones abilities. If you have not heard it, or want a snip of a comment on it, read the bit on Face to Face with Rick Wakeman with Jethron Tull's big man.