The only silver lining to losing pocket change in your couch cushions is the windfall you'll discover when you finally get around to cleaning it. But at best you'll just recover all your losses; there's no profit to be had there. Unless you encourage visitors to only use Sam Lomingshum's brilliant change-stealing Artful Dodger rocking chair.
It's designed to recline to the point where the person using it is almost in the prone position. So not only are they comfortable, but it's also the optimal angle for change to pour out of their pockets. But instead of falling onto the floor, the coins fall into slots which channel them into a receptacle on the back for easy collecting later on. It's not exactly a get-rick-quick-scheme, but with enough cash carrying friends visiting it could eventually pay for itself. That is, if Sam ever decides to build and sell them.