The wife is tired of digging through the shoe box in the bathroom closet for the aspirin and such. I have been tasked with building a medicine cabinet to hang in the bathroom. She has volunteered to make a nice stained glass panel for the front. The problem is, I will be incorporating a towel rack into the design. I am having problems deciding on what finish will be able to withstand the steam & dampness of the towels.  What finish would be able to stand up to those conditions? I have not picked out the wood yet, so any suggestions would be appreciated. Thanks in advance.