Custom hand painted HGU-55/55P flight helmets are something that I started doing a couple years ago and they've generated a really good response.  Each is done with acrylic paint and sealed with crystal clear gloss.  If you're interested having one done, you'll need to provide the helmet and the concept.  Include your unit patches, aircraft flown, favorite sports team logos, favorite whisky...it's all fair game.  Contact me for pricing and further details!