A really fun side-line that I do during Christmas season is hand-painted glass ornaments. They allow me to offer a smaller, less expensive item in my booth, plus they do wonders for my drawing skills.I think of it as a sort of yearly "drawing bootcamp"...no erasing possible, plus the added challenge of working on a sphere!
Here are some photos of the crop I did for my yearly Open Studio Show:
They are notoriously hard to photograph, with the images wrapping all the way around behind, and reflections washing everything out...but the general idea is there.