I would also like to advertise localbitcoins.com "flyer" functionality. If you create an advertisement, and go to edit it, you see "Print Flyer" button. With this, you get a nice PDF, which you can print out and attach to local billboard.
The additional benefit is, that you can also make money selling the coins for profit, and also spread the bitcoin love at the same time
Example from my ad:
http://imgur.com/qWrXN