The thing about drawing in public: You get occasional weird looks. In this case, though, I think the kid watching was actually interested.
Here's the finished product. I'm not exactly sure why I enjoy drawing variations of the archetypal "Gray" alien, but it probably has to do with their iconic simplicity and anthropomorphosized sense of otherness.
I'm thinking of preparing an online sketch diary to help take the place of my old doodle gallery. Watch this space.