I thought I'd start a thread for prospective YC winter '10 applicants to share their response to the question: What is your company going to make? Perhaps we could use this as an opportunity to get some feeback from YC alum and the community on the description of your startup's idea/product. Here it goes...<p>Say Hi! connects you to people and places nearby using your cell phone. You can pinpoint your current location, search for new friends or businesses, and exchange chat messages. It’s like a phonebook that gets updated wherever you go.