http://www.youtube.com/watch?v=toHZJQrI5-Q
Watching the NFL combine the last few years - they have the ability to take any guys they want to - and run them side by side.
For instance - when they took the fastest running backs - and had them race against each other... you could see that Alabama RB Mark Ingram finished last of the bunch but beat everyone to the 10-yard split. They could even compare the commentators racing anyone.
Say a track runs five different 6fs races one day - it would be slick to see the winner of each race running against each other. Obviously - you can figure out what it would look like in your head by studying fractional times and doing math ... but still ... if this technology happens to be very cheap and simple ... tracks should make use of it.