My wife an I just got done watching the new Kurt Cobain documentary "montage of heck" and I was sitting there thinking about how Nevermind was such an impressive album. It's simple but brilliant, just a well written piece of art.

Here are some of my favorites (no particular order):

Beatles - Abby Road
Radiohead - OK Computer (Kid A is great as well)
Coltrane - Blue Train
Beck - Sea Change
Elton John - Madman Across the Water
Bela Fleck & the Flecktons - 1st Album
Pat Metheny - Imaginary Day
Nirvana - Nevermind
Rage against the Machine - 1st Album
NIN - Pretty Hate Machine
Pink Floyd - Dark Side of the Moon

Anyway, just first few that came to mind.

Few more:

Bob Marley - Exodus
Queen - Night at the Opera
B. Boys - Paul's Boutique
U2 - Joshua Tree
The Cure - Kiss me Kiss me Kiss me
Ozomatli - 1st album
Beethoven - 9th symphony