Here's a bit of an update...
According to a fellow digger:
source:
http://digg.com/mods/Strange_Ways_to_Unlock_Car_Doors
by fashnek on 5/30/07
So yes, I agree this must be total BS. I'm also convinced that the tennis ball trick will do nothing more than ruin a good tennis ball, and possibly dent the area around the door mechanism.
A couple other neat related ideas if anyone cares. The first vid on this next page seems to hold up, but it's an app written for the RAZR
http://www.techeblog.com/index.php/t...lock-car-doors