Right now there is a Kickstarter campaign going on for a device conceived by John Litschert, a resident of Fort Collins and biomechanist/sports scientist for the US Olympic Training Center. The device, dubbed runScribe, measures stride rate and length, impact Gs, braking Gs, pronation excusion and velocity, contact time and speed—useful metrics for getting insight as to how you run and what changes you could make in order to run faster and more injury-free.
A couple months ago I participated in a running study using runScribe, as described in this post on my personal blog. I came away not only impressed with the device, but also learned things about my running form I did not know before despite running for decades.
The device itself seems reasonably priced ($100-$140) and is available on Kickstarter until Friday, September 19th. It was even a Kickstarter Staff Pick. Check it out!