I get asked that a lot--check it out!
http://www.youtube.com/watch_popup?v=x3Bf0WhvsNk&vq=medium
Seriously--this took place on the Wabash River--not on Lake Manitou.
Couldn't resist it, though.
My wife and I have enjoyed this island immensely these last twenty years. We hope these notes may give you a sense of this special place--and that you may fall under its spell too.