Here's Straight Edge by Minor Threat. Very easy to play, and fun!

e-|-----verse-x6-----|---chorus-x4-----| 
B-|------------------|-----------------| 
G-|------3-3---------|-5-5-5--3--------| 
D-|-5-5--3-3---------|-5-5-5--3--3-----| 
A-|-5-5--1-1---------|-3-3-3--1--3-----| 
E-|-3-3--------------|-----------1-----| 

e-|------endchorus-x4-------| 
B-|-------------------------| 
G-|-7-7-7--5----------------| 
D-|-7-7-7--5--5-------------| 
A-|-5-5-5--3--5-------------| 
E-|-----------3-------------|