Three observations: 1) Redundant Scheduling As an AR.org client, I would not revel in the idea of entering an appointment more than once; it also needs to sho

Three observations: 1) Redundant Scheduling As an AR.org client, I would not revel in the idea of entering an appointment more than once; it also needs to show up in my normal "scheduling" calendar. Possible/partial solution: Google Calendar http://code.google.com/apis/calendar/ http://code.google.com/apis/calendar/ 2) Zipcar - example #1 They have a very effective implementation of an app that schedules/extends your car appointment via SMS. It has saved me a $50 penalty on more than one occasion. 3) Time Warner Cable - example #2 TWC has an automated call reminding customers when they have an appointment; may be worth investigating. Anecdotally, as a reminder, it has been most handy when an appointment was made a week or more in the future. Of c. 7 appointments over 6 years, I think it effectively reminded me to reschedule 1 of the two appointments I had to reschedule. One last thought; two factors seem to be driving your choice of business: (1) a focus on under-served niches, parlaying your marketing savvy and (2) unsexy businesses, reducing the potential for competition from technically skilled entrepreneurs... a very practical approach! Anyway, best of luck.