The idiot drivers that move steadily along, but suddenly increase speed when they wake up and realize you are passing them. If they succeed in blocking your opportunity to pass, they will immediately resume the former, annoying pace. If you pass them successfully, they will ride your bumper for a short time before returning to la-la land.
> That's right you F%$&!@# passhole. Suddenly you're in a big F%$&!@# hurry!