I came across an awesome Gizmo costume pattern from the 80's - McCalls 9255. But it's printed in children's sizes and I am an adult XXL. Using the pattern and pictures as inspiration, here is my best version:
This year I made a banana slug costume to wear during our Halloween storytime session at the library (I'm a children's librarian). I've had bad luck with relatively mild costumes scaring children in the past (think lamb, bunny, lobster with winter mittens), but I've discovered that kids respond well to yellow.
Apparently, so does my cockatiel.
Thanks for looking!
Please forgive my I-stayed-up-all-night-to-make-this face.