A few days ago, I was in conversation about how we all seem to "tune out" various objects, people and happenings from our vision. Selective blindness, I suppose. One of my habitual blindspots is the electric toothbrush in our bathroom. I know it's there. It's where it always is. But about twice a week it'll take me a full minute of staring before I can locate it right under my very nose.

A little later, I was perusing a blog, and the blogger in question mentioned a curious hobby – collecting individual playing cards she finds left in the street.

Since she was told about the strange phenomenon, she's been finding discarded aces, queens and jacks all over the place.

Pah! I thought. Who discards a single playing card? And just how many card-carrying, street-wandering litterbugs can there possibly be?

Sure enough, later that same day I was walking down the street when something caught my eye in the gutter…

What the…?

Perhaps I, too, can build up an entire deck of crumpled, mismatched cards. What will happen when I complete the set? Will a strange, poker-faced wizard pop out from a bush and challenge me to a magical game of Texas Hold'em? Will I gain access to an unearthly secret society? Who knows?

In the meantime, I think I'll try and see if the same principle works for ten-pound notes. So keep an eye out for any flittering across the pavement. If it works, and you become filthy rich, just remember who it was who lifted your veil of selective blindness.