I'm about to dive into a revamp of the payment processing engine for a
my company's software application service. I came across a tool called
Service Merchant (http://servicemerchant.org), and it looks like it
could be a good fit for me, especially since we do recurring monthly
subscription billing.
Has anyone tried using it? Liked it? Any suggestions or comments?
You might also take a look at http://railskits.com/saas/ – it isn’t free, but it has more features, more use in live applications, ongoing support, and a great community of people using it.
I'm one of Service Merchant developers. We're trying to build active
community around the toolkit, so I would be happy to help you if you
become one of the early adopters.