Mixing object-oriented and functional programming

Question

What languages are available that promote both object-oriented and functional programming? I know that any language that supports first-class functions can be considered fun

Answer 1

C#. It's imperative, which can be handy, but also has a lot of functional features. Lambdas, iterators, and LINQ are all functional.

It probably won't appeal much to purists, but it works for me.