From the ice cream vendor,
Buy two get one free,
Two cones of vanilla ice cream and get a strawberry ice cream cone free.
And if you buy two cones of chocolate ice cream with that you get one cone of butterscotch free.
The flavours could be interchanged too.
As soon as this advertisement went viral,
People flocked to his shop like bees attracted to honey.
He soon ran out of his stock,
And a week later he had to keep an extra helper in his shop,
His shop became a super duper hit.
And his sales excelled hereafter.