Being a ribbon whore/hoarder, I have plenty of grosgrain stash to make the (say it in a high-pitched tone) fabulous cosmetic bags!
Sew some ribbons together then add a zipper. With right sides together, sew one narrow side and long side. Make sure the zipper is open. Fold other narrow side and sew. 
(Wish like heck I could give credit for the concept but I cannot remember the ribbon craft book title.)
Craft supply suggestion: buy in bulk from eBay.
