After getting $100 in free advertising coupons ($50 from godaddy and a $50 coupon i found online), i thought i would try it out and see how fast i could use up the $100. I setup my CPC at $0.05, and within 24 hours, all $100 was spent (Thats 2000 clicks), and i had actually made about $350 in ad clicks and payments VIA my facebook application. All in all, i turned a $250 "profit" ($350 really, as i dident spend any actual money), and keep taking 1/4 of all earnings and throwing it back into the ad platform, and i'm making a pretty steady stream of cash. Just make sure that if you do use coupons, just to get the free ad's, make sure you set your campaign to a MAX of the coupon amount, or you will be billed it get's eaten up really fast.
one thing i forgot to mention: For those w/o credit cards, don't worry! You can buy a prepaid mastercard/visa and use that Also, coupons only work on U.S Currency accounts
I haven't seen them charge anything less than .15 per click on any of their ads. If you have it at .05 cents.. you will not get any impressions. This is definitely a joke.