The DJ invites all married couple onto the dance floor. As time goes by he asks couples married for one day to step off, then couples married for one year to step off the dance fllor, etc. The couple still dancing at the end of the song has been married the longest. Everyone claps and congratulates them for lasting so long and you present them witjh a bouqet of flowers your florist providid.
I am going to do this. Its kinda fun trying to guess who will be the last couple.