Really neat stuff here, directly applicable to what many of us are doing.
A GM researcher shows off shape memory alloys to Autoline Detroit TV host along with three potential automotive applications - 2 of which are active aerodynamics.
The alloys can be stretched, and return to their "memory" shape with the application of heat (or electrical current). So you can create opposing shape memory springs, and by alternately heating one or the other, move stuff (like grille louvers).