Ask HN: Small business software that is primed for disruption?

I just got word today that the company I work for is splitting in two and the project I've been working on for 2 years is going one way, while my employer goes another. I have the option of following the project or staying where I am and, thus far, I'm opting to stay where I am. I've been reassured that there is plenty of work to do outside of this particular project, but the company will be looking for new spaces that we can be potentially disrupt and I've been tapped to offer any suggestions I can come up with. They're primarily looking at aging software used by small businesses where there aren't a lot of players or VC funding, and that be can be transitioned from local installs to a web-based system. Some initial thoughts, that may or may not even fit the criteria, were P.O.S. Systems for small restaurants and shops, or Patient/Appointment managing software for small doctor's offices.

I know that the schools of thought on "ideas" are divided between them being worthless without execution or them being potential goldmines if you hit the right one, so I'm hoping to tap the former thinkers on any ideas they might have. I've read PG's startup ideas essay, but I'll review it as well.