I recently just joined “Passionfruit Ads”, I wanted to offer adds on Oh! My Heartsie Reviews but I wanted a way to take care of sponsors that sign up without having to remember when they signed up and when their sponsorship ended. Passionfruit Ads takes care of all of the critical information so I dont have to rely on my memory to do that (getting older has its downfalls) as I didnt want to accidentally delete a sponsor to soon. I also found it is a great way for swapping ads for the same reasons, the ad swaps are completely free.
Passionfruit makes it so easy, just fill out what you want the ad to be and they create the code. You set up a page and give it a title and wallah, you have a page for sponsoring ads. They take care of the billing, rotating ads, removing the ads when they are expired. You also choose how many ads you want to appear. They are very reasonable, no arm & leg in the cost.
If you are interested in swapping ads just email me or check out the Sponsor My Blog page for more ad offers.