Subscription management/billing software?
NoBSWebDesign: We use BlinkSale (http://www.blinksale.com) for invoicing and like it very much. They have a nice interface for creating templates and recurring invoices as well. Though, as I began digging deeper into this area, I've begun to think that there are a lot of sites that do exactly the same thing in exactly the same way. Go with one that's free to begin with, and pay if you like it I suppose.