Ideas for QR codes for auto repair shops

Someone has an interesting thread on QR codes for auto dealers, I didn't want to hijack his thread, so I started a new one.

What do you think about QR codes for non-sexy businesses like auto repair shops. Currently I am finalizing development of a local printable coupon site for my clients and prospects. The thing is, if someone has already come into the auto repair shop, they are already a customer, so I don't see the point of giving them a coupon at this point in the sales process with a QR code. Maybe I am wrong, but the coupon is supposed to bring them in to the shop, not be given to them when they are already in the shop.

Here are some ideas for QR codes in auto repair shops. Please critique them or add to them as you see fit.

Waiting room: People always need distractions in the waiting room.
QR code to their facebook page. Get more likes.
QR code to their Google Places/Yelp/Citysearch review page. - Get more reviews.
QR code to interesting/funny websites that the shop owner could recommend.
QR code for the customer to look up their recommended schedules maintenance for their vehicle. To something like this site:Car Maintenance Schedules, Recalls, and Technical Service Bulletins
QR code to the shops web page where appointments can be scheduled so the customer can bookmark where to go to make their next appointment.

Any other ideas?