Okay, this isn’t using FastLED, so I hope you don’t mind the share. But it would be easy to port it…
http://www.youtube.com/watch?v=y_ScaZsz6aU
I did use animation programming techniques that I picked up from FastLED example code, though. 
I’ve got a thundercloud that I’ll be rolling out for Halloween. It’ll be hanging from our (rather large) Douglas Fir tree.
Well shoot. I updated the video with titles and such, but the link here points to the uncaptioned version. Go to YouTube and search for “Blinky Eyes 2” for the updates.
EDIT: nevermind – I guess I had the old version cached or something. 
Anyone have this code for FastLED?
I’ve been meaning to do a FastLED version, but just haven’t gotten around to it yet. I might try to convert it for Halloween this year.
It shouldn’t be too hard to translate over.