Here's a handful of, in my opinion, perfect or near-perfect albums:
First, my honorable mentions:
Sea Change - Beck
Blue Album - Weezer
OK Computer - Radiohead
In Rainbows - Radiohead
Dark Side of the Moon - Pink Floyd
Gorillaz - Gorillaz
The Black Album - Jay-Z
My Beautiful Dark Twisted Fantasy - Kanye West
Alive 2007 - Daft Punk
Private Press - DJ Shadow
A Cross the Universe - Justice
Wolfgang Amadeus Phoenix - Phoenix
Portishead - Portishead
Odelay! - Beck

Jar of Flies - Alice In Chains

Selected Ambient Works, Volume II - Aphex Twin

Pinkerton - Weezer

Kid A - Radiohead

Since I Left You - The Avalanches

The Wall - Pink Floyd

Cold Water Music - Aim

Licensed To Ill - Beastie Boys

3 Feet High and Rising - De La Soul

Demon Days - Gorillaz

Metaphorical Music - Nujabes

Caught In the Act - Royal Crown Revue

Ocean Machine: Biomech - Devin Townsend

Train of Thought - Dream Theater

Through Silver In Blood - Neurosis

Endtroducing... - DJ Shadow

James Blake - James Blake

The Presets - Apacalypso

Figurehead - The Queenstons

What's the Story, Morning Glory? - Oasis

MTV Unplugged in New York - Nirvana

Live at Leeds - The Who

And I'm gonna leave it that for now. I could go on for days.
Phew.
Edited by Leon Dota - 4/5/12 at 5:30pm