DaveMage
Slumbering in Tsar
Gems:
Older D&D:
Deities & Demigods w/Cthulhu
1e DMG
All of the 1E Adventure modules I own (about 40 I'd guess)
All of the Planescape Line
Undermountain box set
Several of the FR box sets (including Kara-tur)
FR and DL Atlases
Kara-Tur Trail Map
3E/D20
World's Largest Dungeon (great product, and my EN World username is in the thank you credits.
(Simple pleasures, you know...))
I'm sure I'm forgetting some of the gems, but just as twofalls indicated, I like my whole collection.
Older D&D:
Deities & Demigods w/Cthulhu
1e DMG
All of the 1E Adventure modules I own (about 40 I'd guess)
All of the Planescape Line
Undermountain box set
Several of the FR box sets (including Kara-tur)
FR and DL Atlases
Kara-Tur Trail Map
3E/D20
World's Largest Dungeon (great product, and my EN World username is in the thank you credits.

I'm sure I'm forgetting some of the gems, but just as twofalls indicated, I like my whole collection.