We've certainly been talking about the idea. I think that this is positioned a little differently from Mint. People are far more willing to pay for business software (especially the kind that cuts down on manual labour) than they are on personal efficiency software.

I think that leaves us some room to charge a reasonable monthly fee for some premium features. That is an easier, and more direct, business model.

The Mint-style stuff might come later if we have a big enough audience.