Long story, short: My sister told me that she asked her 4 year old what her favorite sport or hobby is, and she said, "Collecting dirty toenails!" I laughed my butt off when I heard that.
So... much to my sister's chagrin... I altered her a small box in which to keep them. There is also enough room for nail-clippers and nail polish, should she so choose to keep more than toenails in here (my sister is hoping....). She loves it. How cool of an aunt am I?! ;-)
Chip stickers: Basic Grey
Box: The Container Store