Came across what I thought was an interesting and handy tool that uses Google Maps to calculate distance for a given route. There seems to be several different variations that can be used. Some have some pretty useful features, others are more simple, but they allow you to lay out a route using Google Maps, satellite imagery, or, on some, USGS topos. It then calculates distance and charts elevation changes.
http://www.gmap-pedometer.com/
http://walking.about.com/library/walk/blgooglemap1.htm
http://www.mapmyrun.com/create_new
The first link has the least other annoying things on the page, but lacks some of the features the other two have. To use the first, once you find your SP, click the "start recording" button, then double-click your points to lay out the route. It also allows you to save your route as a web link.
This probably replicates some technology that is already out there, but it's not bad for a free and easy tool.
Linear Mode
