Lawyers are bastards

Don't Fuck with Lawyers.
My dad is a partner in a smallish law firm. He loves nothing better than annoying people and suppliers who piss him off, nothing bad, just minor spats. He loves doing really pointless but perfectly legal things. This is my absolute favourite petty revenge story of all time.
Dad has queried an outstanding payment to an office supplier, its about £3800. He contested it and basically dragged out payment for months. Eventually, he agreed that if they sent someone round he'd pay them cash.
In the mean time, he went to the bank and after discussion with the bank manager, worked out what the legal minimum denomination of notes and coins could be used.
He also went to the garden centre and purchased a cheap, yet sturdy black dustbin.
As it turns out, you can pay in coins. the resulting amount pretty much filled the dustbin - well 3/4 full. It was almost impossible to move. 4 guys from the office got it upstairs and hid it in Dad's office. They spent half an hour emptying all the coins from their bags.
The debt collectors arrived. Dad made them wait an hour or so for the hell of it. He came out and spoke to them argued the toss some more. Eventually dad 'caved' and pointed them in the direction of the money. Upon seeing it they groaned and muttered that there's no way they're going to take that. Prepared, Dad immediately hands them a piece of paper and says, fine, sign this. They ask what it is, "its to confirm that I offered you full payment and you refused to accept".
They sigh and give in. Dad asks for a receipt. They start counting. Dad has previously removed a pound or so earlier on.
A couple of hours later, they point out that its a pound down. Dad denies that's possible, maybe they should recount? They relent and fill out a receipt. They fill the bin back up and start dragging it to the lift. My dad watches on.
The lift arrives and they struggle to get it over the floor divider but panting, they finally get the thing in the lift. As the doors begin to close, my dad sticks his hand between the doors, forcing them to open again.
"Erm lads? Where are you going with my bin?"

Nice one Al, wish I had a brain so I could do that.

But as I've not, I resort to a sort of similar 'trick' that works much quicker.

"If you don't fuck off, I'll cut your fuckin head off ok?"

Granted, it's got me into lots of trouble but it definitely gets rid of time wasting cunts.