A famous heart specialist doctor died and everyone was gathered at his funeral. A regular coffin was displayed in front of a huge heart. When the minister finished with the sermon and after everyone said their good-byes, the heart was opened, the coffin rolled inside, and the heart closed.
Just at that moment one of the mourners started laughing. The guy next to him asked: "Why are you laughing?"
"I was thinking about my own funeral" the man replied.
What's the difference between a viola and a coffin?