How to go about offering an offline qr code generating service to local businesses?

I've been reading up on qr codes; I know how to generate a qr code for a website using the goo.gl url shortener, but what I don't know, is how to offer a service generating qr codes for offline businesses. I have some ideas, but because the concept is so new to me, I really don't know the best way to go about doing this.

I also don't know all the things that customers can do with their qr codes. Post them on a website directory? Stick them on telephone poles? Wear them on a badge on their collars?

How would a dentist or doctor create and use a qr code, for example, for a 'next appointment' reminder that a person could zap into their smart phone.

I have researched some of google's api's including:

zxing - Project Hosting on Google Code

QR Code Generator

What I have in mind is a website (plus offline service business) similar to what this site is offering: QR Stuff: Free Printable QR Code Generator, Creator And Encoder For T-Shirts, Labels & Stickers

(At this point in time I can envision a great market for a neon sign with a great big line across the center and big text that says 'No QR Stickers Allowed' on telephone poles, bulletin boards, and other places where folks might get the notion to stick their qr code stickers.) But as far as offering an online qr code repository for local businesses, or a qr code generating service - I need all the help I can get.

Can someone point me in the right direction?