Car chases are ubiquitous in films, and they're usually terrible. A really good car chase can lift a mediocre film into acceptability and can make a good film great.

Best car chase ever? Discuss.

Blankman's favorites:

Ronin- Seeing how it must have been for Princess Diana cruising through the streets and tunnels of Paris at supersonic speeds.
The Italian Job (original)- greatest rooftop car circus ever!
The French Connection- White knuckle terrifying race to beat an elevated train- filmed with no permit, and no insurance!
The Blues Brothers- Just how many Chicago police cars can be destroyed in one film? Apparently all of them.
Bullitt (natch)