I'm not kidding; we might have a career in this! Actually, I should broaden it to 'getting outside' in the city. Paul & I keep finding cash $$$ money on our runs & other outings! I picked up a $5 Monday at 72nd & Harold - would have a photograph of it but it's already in the cash register at DQ. Paul has found a few singles and a larger denomination on the ground during a run and while walking to a cooperative work office. My biggest find was a $20, a couple years ago back home, a surprising rural find.
Nonetheless, we will not be calculating our hourly or per mile rate, or retiring any time soon.