Which functional language?

I want to learn a functional programming language from the Lisp dialect but I'm not sure which one to pick. I want to be able to do practical things with it so I was thinking about Clojure. Does /prog/ have any suggestions?

Lisp isn't all that functional. At least, it tolerates a very non-functional style. Scheme would be better, and Haskell would be better than that.

For education of the "functional style" that is.