I built a site, http://cheapdailyads.com . The premise works like this:
I own several daily message type websites which I advertise in google PPC ads for 1 penny a click and draw about 1000 unique visitors a day. These sites have google ads already hooked in and will cover about 50% of the google PPC ads cost each day. Each daily site asks if the reader would like to receive a daily email with my content every day. On average about 7% of my visitors will sign up for a daily email.
Each daily email that I send has space for advertising several ads and my cheapdailyads.com site is where my advertisers would upload or create their ads that get embedded in each email.
I need someone to step in and get advertisers to advertise their ads in my emails. If you're interested in this idea please contact me. I am willing to partner up with equity.