The PSB M4U 2s are not $100 or less but highly recommended and worth the money. You get what you pay for. These are true noise noise canceling headphones.
http://www.psbspeakers.com/products/...U-2-Headphones
They were named 2012 product of the year by Sound and Vision. Spend a bit extra these may be the last headphones you buy for a decade.