I am developer of MemberWing - free wordpress membership plugin.
After I've included automated payment processing feature via Paypal - the next most frequently asked question was: "is it possible to somehow integrate affiliate program so I could promote my membership site via affiliates?".
This makes perfect sense so I digged a bit into that. Basically for that magic to happen I need to have an existence of service that can do:
recurring subscription payment processing + affiliate tracking + API in one service.
Paypal does all but affiliate tracking.
E-junkie does not do recurring payments support.
Affiliate networks (and least the ones I know of) are missing some part of that required equation as well.
I found one service that seems to have all of these features - click2sell.eu but I know nothing about them. Opinions?
If you know about anyone else that has all the required features - let me know and I'd look into working on that.
Basically if click2sell fees and feedback seems to be reasonable and positive for membership site owners I might look into integrating their system into MemberWing.
If you have suggestions for other services that has these features - I'd be happy to look into them as well.