Just an idea

[XP]

I'm thinking to build a double opt-in mail program for my sites & earn extra bucks from visitors.

I can't trust opt-in mail collector sponsor programs. They are shaving a lot! But maybe someone can open a sponsorship program like this.

Every webmaster will have their own maillist, and Opt-in Master will use their maillist and promote his sites. If there is any sales, webmaster will earn %50 recurring. Or something like this

is it good or bad idea?

[$tandaman]

Well a friend of mine runs a program where you will be able to mail people, and so will he..
you can mail only your own..of course

[andy2000]

maxcash have somthing like that on per signup
that many people use i never made any money
with it when i used on a couple of gallerys though