I _LOVE_ Ummagumma. Put on Granchester Meadows, and I just chill. Astronomy Domonie - ahh. Meddle is also great. What can be said about Dark Side and Wish you were here. Animals is also great, but I'd say 1/2 step down.

Now, you know a real PF fan when they have albums like Atom Heart Mother (Fairly good) and Obscured By Clouds (which I have, but really don't like)