Some of the best Anime intros and endings I've come across (Not in any specific order):

ENJOY!

-Xam'd: Lost Memories (OP)
[link]

-RideBack (ED)
[link]

-Darker Than Black (OP)
[link]

-Chobits (OP)
[link]

-Clannad After Story (OP)
[link]

-Angel Beats (OP)
[link]

-Black Rock Shooter (ED)
[link]

-Mushishi (OP)
[link]

-Gunslinger Girl (OP)
[link]

-Highschool of the Dead (OP)
[link]

Bleach:
-(OP 1)
[link]

-(OP 15)
[link]

-(ED 2)
[link]

-Murder Princess (OP)
[link]

-Air Gear (OP)
[link]

-Blood+ (OP)
[link]

-Casshern Sins (ED)
[link]

-Princess Tutu (OP)
[link]

-Sands of Destruction (OP)
[link]


Heres an extra silly one that i always enjoy watching..

Honey and Clover (OP) --Only the first min er so..--
[link]