I've just come across a service so excellent that I'm going to have to learn some basic coding, just so I can build tools for it. It's called Fire Eagle, and it's going to be mega. Basically it's a location broker. It allows users of GPS enabled mobiles to share their location with other services without having to worry about compromising their privacy and security. Any number of location-based mobile apps are going to be built using this bad-boy, and I've got one in mind. (Anyone with any rails experience is welcome to get in touch. Let's build it!)
Oh, and get this: Fire Eagle is from/been bought by Yahoo. I didn't know they had good ideas anymore.