Good news to those who live in: New York City, Los Angeles, Miami, Honolulu, San Francisco, Chicago, and soon to be Austin. Myopenbar.com has weekly posts listing all the bars that are either: serving free alcohol, specials, cover charges, and special events.
If you are visiting any of these cities, I recommend you check up on this site before you go out. It's fun to go somewhere you've never been or weren't planning on going. This site will aid in the suggestion of a few places. Plus, it's free alcohol, c'mon.