I mean, you can probably guess.

On the publicity trail for Inheritance recently, Rhys Ifans spoke to Collider's Steven Weintraub. (Click through to watch the video.) His answer to this question was maybe surprising but definitely cool:

COLLIDER: There are going to be people out there who have never actually seen your work before. If someone's never seen anything you've done, what is the first thing you'd like them to watch and why?

RHYS IFANS: I would like them to watch a film called Human Nature, directed by Michel Gondry, written by Charlie Kaufman, starring Tim Robbins, Patricia Arquette and myself, and many other great actors. It was a film that kind of came and went a little bit, but it's a film I'm very, very proud of. I'm constantly bumping into people all over the world who've just happened upon it and love it. It's a really lovely film. So off the top of my head, that one. (Source)

It's really not bad, you know.

I think part of the problem was that Michel Gondry wasn't great with English, and at that point in his career Charlie was a little too polite to assert himself and clarify what he wanted. Example: there's a scene in Human Nature that calls for "flash cards." Gondry had never heard of flash cards, so he assumed an electronic card that lights up, and Charlie was all "Yeah... Okay."