I am now selling ad space of my blog labofweb, which has around 7500+ visitors daily and PR-3 and alexa rank below 180K. You can see the smart page rank statics here The cost are very very cheap.You have 4 option, including the 125 x125 banner.the cost are mentioned below 125x125 ads - $4 468x60 ads - $5 ads below post - $4 Footer ad - $3 If you are interested, please PM me