Over the years, I've acquired a ridiculous amount of nail polish. After experimenting with several methods of storage, from makeup bags to dresser drawers, I've found the best way to be something I had all along in my closet: a shoebox. The wide opening allows you to quickly fish out the bottle you are looking for without too much fuss.
A suggestion from my friend K: Wrap your shoebox in a recycled paper bag from the grocery store, flipped inside out. Finish the look with hot-gluing a pretty ribbon to the lid.