There's far too many good ones among my "favourites" for me to pick one above the rest.
But among my all-time favourites, for very different reasons, are: Klaus Schulze, Irrlicht; This Heat, This Heat; Nurse With Wound, Soliloquy for Lilith; Zoviet France, Mohnomishe and Egg, The Polite Force.
( The Mock TurtIe ™ --- Thinks you are a cunt, on, Mon 18 May 2009, 2:02, archived)

I too have many favouriites, but I insist you pick one.

( TBL I posted this on, Mon 18 May 2009, 2:04, archived)

Oh, all right then.
"This Heat", for its sheer stubborn eclecticism.
( The Mock TurtIe ™ --- Thinks you are a cunt, on, Mon 18 May 2009, 2:05, archived)

I never understood the adoration they got....
www.youtube.com/watch?v=bCtecNPQ2zw

I rest my case
( TBL I posted this on, Mon 18 May 2009, 2:07, archived)

Mainly because of the first, self-titled album.
It was such a rough, strange collection, and ran the whole gamut from quiet, creepy barely-music that had obviously been recorded at 3am in a dismal tenement ("Music Like Escaping Gas") to complex hi-tech proto-jungle masterpieces that startle even today ("24 Track Loop").

After the subsequent maxi-single ("Health and Efficiency") and their signing to Rough Trade, things went downhill rapidly - that gig is from their twilight.
( The Mock TurtIe ™ --- Thinks you are a cunt, on, Mon 18 May 2009, 2:14, archived)

I suppose it was an unfair clip to use, but seriously those guys must have been so off thier faces
they were in another dimension to the rest of us. But, I will give you the 1st album as it was indeed strange, and I like strange :-)
( TBL I posted this on, Mon 18 May 2009, 2:17, archived)