When it comes to crime, cops call one piece of evidence "gold." And that one bit of information that really can expedite an investigation is a license plate number. If you see something happen and it doesn't endanger yourself, take note of license plate numbers.

Yesterday in West Covina, a 91-year-old was killed in a hit-and-run accident in a cul-de-sac, which should be some of the safest streets in a neighborhood. "The driver got out, saw the woman on the ground, got back into a minivan and sped off," reported ABC7.

Witnesses standing nearby were calling 911 as it happened, but according to news reports, only a description of the man and vehicle, a minivan, were given. Taking note of a license plate in any situation never hurts. If it ends up being useless, you chuck it, if not, the police have something on file.

Another great tip: According to Captain Jim Miller at the LAPD's Van Nuys Division, taking note of a criminal's shoes is a great piece of suspect description. People can change shirts and pants easily, but how often do they change their shoes?

Photo of the 'Godspeed' License Plate by rick via Flickr