In no real except that which I think of them:
Genesis
Arena
Porcupine Tree
Yes
Godspeed You Black Emperor
Mike Oldfield
Capercaillie
Jose Angel Hevia
Steeleye Span
Marillion
The Beatles
Magnum
The Doors
Renaissance
Celtarabia
The AfroCelt Sound System
All of this list - like life - is subject to change without notice.