I second the streamz. I used to come back from riding with sore ears from the wind but not anymore, and I actually hear the wind going over my ear. INstallation was cake as long as your helmet strap came in 1 of 2 configurations - check their site for instructions. Only thing to note is press the tabs into the strap firmly so they stay put, and to set them near your ear in line withe the wind direction - if your head is tilted down while riding then move the streamz a bit up on the strap.

Of course you can strap some other material like tape in place of the streamz but that doesn't look quite as nice... Besides they're only a couple bucks, what can you lose?