While developing ridefreebikemaps.com I needed to create an elevation profile for the routes. Initially I used the example provided by Google. That worked for a while but after I got a few big updates out of the way I decided to work on the elevation profile more. I had three goals for the profile:
Display elevation data in a graph and exact values when the mouse is over the graph.
Show the location of the elevation data on the map when the mouse is over the graph.
Use the elevation profile to control where the map is divided.
I have achieved all those goals but I don't know if the last one will stick around. Currently it's a hidden feature and I don't think it's useful.
I've never developed anything open source before. The only goal I have for this project is that it gets accepted into the Google chart visualization gallery. Hopefully it will be of some use to people there. I put off developing it for a while because I really didn't care about it when much sexier/larger/important features needed to be worked on.