This is a bit old, but I just discovered it this weekend, so it's new to me: Over at
Dresden's Institute of Technology, they have
an applet which performs a microsimulation of road traffic. While this sounds about as fun as sitting in regular traffic, it actually has a "Sims"-type feel to it, meaning that there is a great amount of enjoyment to be had from the process of making all the (simulated) people in these little cars late for dinner, then releasing them from the perils of gridlock.
The idea of
traffic engineering has always fascinated me. While this doesn't explain any of the concepts behind it, I think it shows that there's a little bit more to traffic than just the chaos and randomness we think there is.
Hit the
Link to check it out.