adzmo
Adzmo is a Rails app I built in 2006. Adzmo was a location shopping tool before smart phones and GPS. It allowed a user to send a txt message or email to [category]@adzmo.com with the telephone number of any nearby store in the body of the message and where category was a product or service they were interested in. The app would look up the telephone number provided in the body, do a reverse lookup, find the address to determine location, then do a local search on Yahoo based on that location and the category of merchant and finally return the results of that search back to the user.
Adzmo.com is a location based shopping tool. By sending a short text message, like the one you see below, adzmo.com can tell you where the closest shops and restaurants are.
Just sent a text message to any category of product, like pizza@adzmo.com. In the body of your message include the phone number of any nearby store, restaurant, or merchant. Within seconds you'll receive a detailed list of nearby merchants matching the category your provided.