The Irish have a looooong history for laying curses. Here's a modern day one that I wrote. I double dog dare ya to come up with better one!
I lay curses on you, you wretched fool!
You'll never find the right-sized tool!
Your breath will smell just like your pits,
On top of that, you'll grow big zits!
You're a hateful bastard, you're oh so vile,
So I'll zap each one of your computer files!
You'll never be able to sign "online"
Nobody loves you, you rotten swine!
I'll make your cat hate you, your dog pass gas
I'll make putrid blisters grow on your ass!
I'll have all your in-laws move in to stay,
And make every day a "bad hair day!"
If that's not enough, you filthy scum,
I'll make hairy warts grow on your tongue!
Your CD's scratch, your libido fail,
I'll curse you to only get chain email!
Your friends will all leave you
To the IRS they'll snitch
Perhaps that will teach you....
NEVER PISS OFF A WITCH!