This map uses cell phone triangulation to approximate my location from my Windows Mobile 6 phone and display my last known position using Google Maps. I switched from using the Reperion service to using Navizon until I have a phone with a gps chip in it. I kept having to pair my gps and start Reperion whenever I got in the car and now that Navizon is allowing free cell tower location, it’s a more elegant solution.

Pinpoint accuracy isn’t necessary for the map to be interesting and some people may question whether posting your location on the web is safe. While I’m going to share the details of how I’m doing this, I don’t recommend giving out your location anywhere. There are tools that allow you to share your location with specific friends and it’s a much safer idea. Letting anyone see where you are is probably unwise and potentially lethal. If you decide to do so, you are responsible for the results.

With that said, I can turn off the Navizon tracking any time I want to and it will not provide updates when I’m out of range. When this happens, the map will continue to display my last known location. You can tell by looking at the timestamp when you click on the marker. I’ll work on getting it to center on the marker and open the info window automatically to help be more specific.

When you sign up for the Navizon service, they provide you with access to your location via an XML web service. Unfortunately it’s not very well formed and certainly not geoxml, georss, or any other kind of standards compliant that I could find. This meant that I had to find a way to extract the details that I was looking for and overlay the information on the map. One of the most obvious ways to do this is using javascript, but I still haven’t mastered using loops to walk to document tree.

This turned out to be my first real foray into Yahoo Pipes. I’ve played with Pipes a few times in the past, but didn’t have the vocabulary to tell it what I wanted. Yahoo Pipes provides a powerful interface for mashing web services. All I did was input the url to retrieve the xml location information and rename a few fields to be readable by the Location Extractor tool. The Location Extractor is an awesome tool because it will find any zip code or address in a data source or web page and turn it into a map for you.

The last thing that I had to do was create a map and overlay the position. Yahoo Pipes allows you to use your data in virtually any format that you want, including rss, xml, JSON or even kml.KML is Google Maps native xml format so once you’ve created a map, you can easily overlay it as a GGeoXML overlay. You can learn how to do this from the Google Maps API documentation.

Now that I’ve learned more about mashing data using Pipes, it’s gotten me thinking about other potential projects. Maybe I can include my Twitter posts into the information window? Then maybe have the official theregoesdave Google Gadget? That way people could experience this site as a location based blog!?