My head is big. This means most hats don't fit. And adding my long hair, you need to add a size or two to that. Which is why few of the ski helmets with built-in headphones fit me, not to mention comfortably. And considering what you need to pay extra for that feature, I figured I better buy a helmet that fits my head and then modify it. Which is what I did some years back. Using some duct tape, thread and a set €15/$20 head phones I had a helmet that allowed me to listen to music on my iPod while in the ski lift.