Layla

Rock song by Eric Clapton. Was about the wife of a friend that he loved, and later married...and later divorced. Still one of the best songs of all time. Theres the normal version and a accoustic or unplugged version.
Layla! You got me on my knees! Layla!

Here are the main guitar licks in the song..

_backup_
dm                    Bb     C      dm
---------------------------------------|-------------------
---------------------------------------|-------------------
----------------7--5--3------5------7--|-------------------
-----0-3-0---0--7--5--3------5------7--|-------------------
-0-3-------3----5--3--1-0----3-0----5--|-------------------
--------------------------1------3-----|-------------------
_lead_
------------------------17-15--------------|---------------
--------15-18-15----15--------18-17-17-15--|---------------
--14-17----------17------------------------|---------------
-------------------------------------------|---------------
-------------------------------------------|---------------
-------------------------------------------|---------------

_2nd lead_ (same as the first, a fifth up.. this is 
actually not in the song, but I think it sounds cool.. blah)
---------------------10--8----------------|----------------
--------8-11-8----8--------11-10----8-----|----------------
--7--10--------10----------------10-------|----------------
------------------------------------------|----------------
------------------------------------------|----------------
------------------------------------------|----------------

(more to come soon)

The friend whose wife that the song was written about just happened to be George Harrison, lead guitarist for The Beatles. As is said above, Eric eventually did marry her (her actual name was Pattie). The relationship between Patti and Eric caused George to get very upset, and greatly strained the friendship of the two (as one would expect).

Also, the song was originally performed by Derek and the Dominoes, one of Eric Clapton's many groups. It appeared on their only studio album, Layla and Other Assorted Love Songs.