According to the completely authoritative sources of youtube and metacafe, you can extend the range of your car remote by holding the remote to your head. It’s easy enough to test, and if it works it could come in handy for finding your car in the parking lot. So far, I’ve found two videos demonstrating the hack, and both use a slightly different method.
In one method you simply touch the remote to your noggin – Link.
In the other video, a more sophisticated open mouth, below the chin technique is used – Link.
I’m guessing that your head is acting as a crude directional antenna, but if you know more about how this works, let us know in the comments.