What are the best uses for a kitchen island?

[Dover]

I know this is going to be an individual thing, but I don't have an island (yet) and wonder how best to use one.
For instance, is it best to have a sink in it or keep it as a dry work area only? What about putting a stove
top on it? Is it a good place to put a dishwasher?

I'm asking questions like this because I'm designing a new kitchen and need to think about how to configure it.
It's not a huge space, but big enough for an island if I choose to add one. What is on your island and how has
it worked for you?

Maybe there's a good book out there
that covers this subject.