I have started selling 125*125 ads on my PR4 tech website: www.NetbookFreeware.com. This is a PR4 website, and gets 7000 visits, and 17000 page views monthly. The ads will be visible on Right sidebar, below "Subscribe" section. It will be visible on all pages, including Home Page. I am offering a huge discount right now as I have just started selling the ads. Right now, you can buy this ad spot for just $5 per month! This is the lowest advertising price that I have seen on a PR4 website. PM me for any other details.