I recently read a post here about trying to start an email campaign based on the sales you make on your eBay account. Basically, I imagine you build up a list of who bought what. Then you can send them emails related to their interests based on what they bought. What I'm sure of right now is what would be the best method to monetize from such an email campaign? Is there anything particular that you found would work best on customers of eBay sales? For example, the only thing I can think of right now is signing up with an affiliate company and sending them my affiliate link and trying to make something extra that way. But I'm sure there must be better ways to monetize this method?