For years, our family would spread butter on the corn on the cob with a knife.
I always sat there at the table wondering why the heck there wasn't a better way to do it, since everyone's butter just slid of the corn onto the plate.
Then, in my teens I think, my Mother began putting a small dish of melted butter and a pastry brush on the table. But by the time you finished spreading melted butter on the corn on the cob, it had all dripped onto the plate. So I'd wait patiently for everyone to be finished with the butter and I'd just keep buttering my corn on the cob until I was finished eating it. Yeah I know, that's like double dipping, but I always thought this method should thrown out.
I still eat dinner with my family on weekends, and like someone else in this thread said, my Mother (finally ) bought the gadget that holds a stick of butter and this is by far the best method yet.