I got a pitch for Quick Books SDK in my e-mail today. We might get into this area at some point. We have a vertical app that doesn't claim to do accounting, but knows an awful lot about your receivables and wouldn't mind keying them in for you if your accounting software was inclined to let us.

My question is this:

What other low to mid price accounting packages provide some means for a programmer to enter data directly in and avoid double keying?