This ALEX Drawer unit from IKEA fits perfectly between my vanity and the wall - will hold lots of make-up and hair goodies. $119 and paintable! Will paint with the bathroom wall color (stony-taupe). May stencil with a large flowy fleur de lis inspired design in a dark cocoa brown to match our vanities.
For an easy and inexpensive bathroom storage solution, consider retrofitting an existing vanity with a storage unit placed on the countertop. Here, a slender but versatile piece of cabinetry sits between the vanity's two sinks, providing open and closed storage at arm's length. The cabinet was topped with crown molding to give it a built-in look.