The Futurama ep "Bender's Game" has a great Yellow Submarine tribute animation.

I wanna watch the whole thing again just cause I love Walter Bishop so much (I love that in the first episode he wanted a cow just to watch cartoons with it).  John Noble got to do so much with Walter, he starts as this hurt, scared, lost individual, then you get Walternate who's cold and cruel and you realize just how much range all this actor can bring to the table.  I also just adore Parallel Universe Astrid, she's so cute!  Actually dig all the actors in this, I really do hope that they all do something together again like a romantic comedy or something, they're fun to watch together and so bloody talented.

I have to say one of the things in the series that won me over was the opening sequence, at first I didn't get it, but then we start seeing these alternate versions (I love the VHS-y 80s version) and I "got" what it was supposed to be.