Gary tells us he came up with the idea to write his "money back message" in 2003 when he had some health problems and took some time off from work.

Since then, every time he goes to the market, gas station or convenience store, he pays with dollar bills that one day make their way right back into his wallet.

"People are more likely to send one dollar back than they would 5, 10, 20, 50 or 100."

Gary averages about $2 a day and every so often someone will throw in a cash bonus. Last month, he made $60 and the month before $94.