Three's a crowd, so they say. On the other hand, don't all good things come in threes? When we think of a trio, music acts like the Three Tenors or the Bee Gees often spring to mind. But a trio can also mean a group of things. In fact, it's a reference to absolutely anything that exists in the number three. So, how many three of a kinds do you know?
Click through and take a look at these famous trios.