In the "redd" thread of W&F, wow invoked:
See a penny, pick it up,
All the day you'll have good luck.
OR
Find a penny, give it away,
Luck will follow you all the day.

This made me think of a custom that I wasn't privy to until college... one of my friends would only pick up pennies if they were head side up (although it might be noted here that she'd pick up coins of any other denomination, regardless of the heads or tails issue - obviously this wouldn't even enter her mind if she came across a $20).

Now, wow's first version of the rhyme, which is the one I learned, puts no conditions on the penny/luck correlation. Has anyone else heard of this custom/superstition?