Your favorite prog rock music? ?

I used to be a real maven on the subject-I've aged and gone in different directions. I can, however, give u some ideas:

Yes-Close to the Edge and Topographic Oceans (Latter is a controversial choice as many hate it)
Genesis-Selling England (A killer great work)
ELP-Tarkus (Most would say Brain Salad)
Hawkwind-Space Ritual (Trust me, it's an original. By the way, "do not panic".)
Pink Floyd-Meddle
Tull-Thick as a Brick (It's progressive, I guess, but more in the "art" camp)

This is a decent start.

Let me add to my list the following:

King Crimson-Starless and Bible Black (heavy)
King Crimson-Larks Tongues (really heavy)
Strawbs-Hero and Heroine (folky elements in this band add character to the prog feel)
Eno-Another Green World (really more "ambient" than prog)
Moodies-Question of Balance
Nektar-Remember the Future

Queen - pomp and operatic rock.
Rush 2112 was a classic too

good thread!

DOESN'T ANYONE REMEMBER RENAISSANCE, THE BEST GROUP OF THEM ALL?

You guys listed all of mine except Renaissance. Most specifically "Ashes Are Burning" and "Turn of the Cards".

I would also add Alan Parsons, Caravan, Camel and It's a Beautiful Day.