Just in case this site isn't nerdy enough, I'll make a list of manga, comics, and graphic novels that I think everyone should read. If you think I'm missing something, just email me a title or a link to a site with scans.
psychoxlobotomy@aol.com
Manga (some are anime shows, too)
Bleach
Chobits
Death Note
Dice
DNAngel
D.Gray-Man
Fullmetal Alchemist
Kingdom Hearts (The manga slightly differs from the game. It's quite funny)
Legal Drug
Legend of Mana
Naruto
One Piece
Ouran High School Host Club
Twin Signal
Zatch Bell
Zoids
Comics
JtHM (Johnny the Homicidal Maniac)
Squee!
I Feel Sick
Lenore
Batman: Arkham Asylum
Other Graphic Novels
The Clarence Principle
Something at the Window is Scratching
The Monsters in my Tummy
The Cat with the Really Big Head (and two other stories that aren't as great)