[Haskell-cafe] A good video on monad

Hi, I found this nice video on monads (although for clojure). http://www.youtube.com/watch?v=ObR3qi4Guys Question - in the video, if I understood right, the guy implements "return" as a function that takes a value and returns a function (action) that takes nothing and returns that value. And upon executing the action (essentially invoking the function that takes void) you get the value. So, what is the correct way of thinking about the similarity(if any) between a function taking 0 parameters and a single parameter type constructor? Regards, Kashyap