Tickets by phone
First you could buy movie tickets via the web and pick them up at the theater. Then you could print the tickets and bring them with you. Now you can buy concert tickets on your phone. Even cooler is that you receive the ticket as an image (or text for older phones) via SMS. The image has a barcode that can be scanned at the gate (or a unique ID for text messages).
If anyone wants to make “m-commerce” work, they need to focus on the kind of thing people buy on short notice. The ability to look up movie times, then buy tickets form my phone actually makes me want to use the stupid browser my phone has. Anything that lets me find a movie on short notice then buy the tickets without waiting in line is something I wholly support.
update: Forgot to mention that I was talking about cell phones…