I like this one except that you really can't get a feel for what it is unless it's on its back. Hanging it from a string or something so that it appears to be flying would work well.

Difficulty : Beginner-Intermediate
Number of Bills : 2
Denomination Recommended : Any
Credits : Origami with Dollar Bills by Duy Nguyen.

Diagram [PDF] (currently none available)

Bottom Side
Bat - Fruit 01-01
Bottom
Bat - Fruit 01-02
Back
Bat - Fruit 01-03
Parts Top
Bat - Fruit 01-04
Parts Side
Bat - Fruit 01-05