Nearly every Taco Bell has a charity box that doubles as a game for patrons to dump their excess change. If you are able to land a coin on the lowest ledge, you win a free taco. Most people simply drop the change, hope for the best, but assume the only tacos they will be enjoying are the ones they just ordered.
But Jawa044 explains how to win at the coin drop game in this video from 2008 that is trending again now.