With all this talk about higher order functions: Nearly all OO programming languages support higher order objects!
(Which are objects that take other objects to perform a task)
Higher order functions might be a big "Ah" moment in FP, but the concept is really very simple and basic in OO.
Update: Dear Dzone readers, there is not much content here, because there is not much to say. OO languages support higher order objects. Thanks.
Update 2: Functions take values as parameters. Functions which take functions as parameters are called higher order functions. Objects take values as parameters. Objects which take objects as paramaters are higher order objects. As the concept is very basic in OO, people don't talk about it.
Update 3: As commented, a function is also higher order when it returns a function. "A function that takes a function as an argument, or returns a function as a result". Same goes for higher order objects (those returning an object in a method)