I'm selling ads on http://tiny.cc/pEukN. I'm accepting banner sizes as big as 500 x 500. Ads will run for one full week. Blog gets well over 21 thousand page views a month and is currently getting 2k unique visitors a week. The stats have been increasing ever since I started the blog over 8 months ago. I offer a $5 discount if you buy a full month of ad space.