Herbie and all associated characters are owned by Disney.
Buffy the Vampire Slayer and all associated characters were created by Joss Whedon and are owned by Mutant Enemy.
This is just me answering one of my own challenges, so utter crack-fic ahead...
Herbie goes to the Hellmouth
"Well, this is good..." Xander edged away from the door as a vampire slammed into it, trying to smash the thin glass window, "As ever, proof that no good deed goes unpunished on the Hellmouth..."
"You'd rather Buffy taught me to drive?" Dawn asked, making sure for the tenth time that her door was locked securely, "And you're the one who convinced me to by a Bug in the first place; I wanted that SUV!" She turned to look at her friend and long-time object of lust, "We wouldn't have this problem in an SUV!"
"You're still on your learners permit; you can't legally drive an SUV." Xander pointed out; searching through the gear on the back seat, "Don't suppose you've got any stakes in here?"
"Yeah; an entire bag of them." Dawn banged her head against the steering wheel, setting the horn off, "In the trunk, which is for some reason at the front, thus inaccessible from inside the car."
"And we both forgot our cell phones, thus breaking rule number two for living on a Hellmouth." Xander sunk back into his seat, "We are so dead unless Buffy swings by this way on her patrol...of all the places to run out of gas!"
There was a strange clunk from the front of the car, and it started to bounce up and down of its own accorded. The hood flipped open and something flew through the air so fast it blurred: it struck a vampire right in the heart, and he exploded into a rather surprised looking cloud of dust.
"What in the name of Jesse James..." Xander blinked as the hood opened and closed again and again, and several more vampires disappear as they were hit by stakes thrown with pint-point accuracy. There was a loud bang and then the engine roared to life, sounding much better than it had at any time since they had picked it out at the Sunnydale used car lot. The radio came to life, flicking through the stations until it stopped on one playing an instrumental version of 'I Can't Turn You Lose' by Ottis Redding.
"Our Lady of Blessed Acceleration, don't fail us now!" Dawn put her foot down on the accelerator as hard as she could, the small car's tires kicking up twin trails of mud and grass as she steered it along the dirt road leading through the cemetery. Vampires dived for safety, many caught by the steady stream of stakes still emanating from under the hood.
"Got a lot more power than I gave it credit for!" Xander grabbed the dashboard in a bid to stop himself being thrown out of his seat, "Want to slow down a little?"
"It's not me!" Dawn took her hands off the wheel; it continued turning of its own accord, "What was it that note said?"
"Please take care of Herbie. Whatever your problems, he will help you solve them." Xander closed his eyes to call up the memory, glad for the distraction, "God is mocking me..."