Check out Rob Bjornson's (Bayou Bleu) page about using GPS loggers to record races.  The loggers are available for less than $100 now, and record your position every second.  The results can be downloaded and combined to replay entire regattas, if enough of us get trackers.

To cut to the chase, here is a short  movie of Bayou Bleu's start from 5/27. Note that it looks better when you run the actual software.  

Here is a link to Rob's wiki page that has more detail about how this works, and also has longer movies showing actual races: http://maguro.cs.yale.edu:8000/GpsLogger