We're a promo company that has started to create web tools at client's requests and have some potential tools to sell on a more broad scale that surprisingly no one else has created. Any ideas what kind of residual/percentage/revenue sharing to offer my developers?

I mean, we would always do the sales, support, take client calls, emails...

The developers would only need to sit back and make an occasional update, y'know? At the same time, we want to give enough so that the developer stays interested in the project and in making updates when needed.

Thanks in advance.