Not everyone carries air pistol pellets
My favourite is to take a match. Break it in half, and throw one half away. With the remaining half, break it again, but not all the way through so that you can bend it to make a V shape.

Now take off the dust cap. Push the bent match into the dust cap, so that the base of the V is pointing down.

Now replace the dust cap. The tyre will deflate.

When the car driver notices the flat, he takes it to a garage, inflates tyre, and replaces cap. Repeats ad infinitum. Nobody ever looks in the cap for a foreign body.

Resist the urge to do all four tyres as this makes it suspicious.

For a quick fix... just pour a bottle of brake-fluid over the bonnet.
( Piper Alpha is being a grumpy northerm bastard on:, Fri 30 Apr 2010, 8:36, 1 reply)

I'm going to count how many times I have to say this during this QOTW.
... "or, you could man the fuck up, stop being such a pathetic passive-aggressive arse, accept that fact that parking in the wrong space (delete as applicable dependent on perceived sleight) is a crime somewhere lower in the scheme of things than dialing a wrong number, and politely ask the person concerned to not do it again?"

Twice so far, and I've only read about 10 posts. Place your bets, ladies and jellyspoons.

EDIT - although I will grudgingly admit that the matchstick thing is quite clever.
( the mighty badger Aphrodite, on a bar stool, by your side, Fri 30 Apr 2010, 8:52, closed)

I'm a cyclist
I don't give a flying one about car parking spaces.

But I do like ve-hick-el saboutage.
( Piper Alpha is being a grumpy northerm bastard on:, Fri 30 Apr 2010, 14:29, closed)

I'm cycling to work tomorrow
No parking, no petrol, no walk across a car park, just 10 minutes door-to-door. Good times.

Must remember to take off the bike clips this time.
(Juan Quar is clinging to her front teeth on, Fri 30 Apr 2010, 21:14, closed)