a recurred billing product can be something like a membership site. so if your offering a service like making templates or giving advice but changing things every month, you can set up recurring billing. and you can charge your customers a certain amount every month.
These are also called membership sites - where someone charges a monthly fee for access to a private forum, site, blog, etc. Affiliate programs with recurring billing are great to promote because you only have to make the sale once and usually you get paid multiple times - each month, for as long as the person remains part of the membership site. There are also services that charge a monthly fee - think online game rental, movie rental, that type of thing. You'll find lots of recurring billing programs in the Internet marketing category as well. The gurus often charge big bucks and provide juicy commissions for their affiliates when they are running a membership site. Dan
These are common in Webhosting and Membership companies. Instead of paying a 1-time fee, you will be billed monthly/weekly/yearly on a product or service.
The product can be anything especially virtual item such as service. You can even bill recurring fee for physical product let say house renting fee.The renter pay you a certain sum per month in order to stay in the house owned by you.
These products are subscription based, so mobile ringtones for example are recurring billing, or magazine subscriptions. Yes a service can be one, an account would be recurring billing or website manager/designer can be recurring if you need it updating regular.