MIT has put GPSs on their shuttle buses and shows
bus locations via the web so you can minimize
your wait time,

  http://shuttletrack.mit.edu/allroutes.php

The backend is Perl and the front end is PHP,

  http://shuttletrack.mit.edu/code.php

They offer a challenge: "You think you can do
something more efficiently? Let us know."

Regards,
--
Bil Kleb
http://fun3d.larc.nasa.gov