I autocrossed this past Saturday (I won our stock street tire class) and carried along with me a rented Traqmate. Traqmate is really cool in that it tracks the car using GPS and also records the lateral loads (g forces).

If anyone is interested in checking out the files go here. The free program to interpret the files is here and the manual to use it is here. My runs are under 80-AT and my wife ran under 180-AT.

We also took video of our runs. That posting is here.