Here is something that I made up off the top of my head:

e------------------------------------------------------------------------------------
A------------------------------------------------------------------------------------
D------------------------------------------------------------------------------------
G------------------------------------------------------------------------------------
B------------------------------------------------------------------------------------
E--3-0-0-0-5-0-0-0-6-0-0-0-5-0-3-0-1-0-0-0-3-0-0-0-5-0-0-0-6-0-5-0-3-0-0-0-----------

You can repeat this until you get bored and the tune is stuck in your head forever.