18 pennies.

I was having coffee at a local diner the other day and this little boy was playing with his coins. He put a quarter on his elbow and asked me if I could catch it - you know, like the Fonz did in that Happy Days episode. So I obliged the child. He was impressed. I stopped at 18 cents. Didn't wanna burst the lad's bubble.

NOTE: Stacking the pennies on my elbow for this picture was a 100x harder than catching them in my hand.