Forget swimming, soccer and water polo, the No. 1 spectator sport of the Olympics has begun: pin trading.

This year Coca-Cola, the longest continuous Olympic sponsor, will release 182 co-branded pins. Among these will be 17 Pin of the Day pins, that, when pieced together, form a Coke bottle.

Commemorative lapel pins have been a part of the Olympic tradition since the first modern Games took place in Athens in 1896.