This is what most of us use. Mount with Velcro or double sided spongey tape. Doesn't swivel, costs a bit, but always works and never runs out of battery. Dimmable white and color light, and an IFF flasher visible under goggles.
http://www.surefire.com/illumination/helmet-lights.html
That, or a headlamp taped to the visor cover. But those look cheap.
Mike