NoSweat's line of peel-and-stick hardhat liners are designed to wick away up to 2oz of sweat and prevent dripping. Check them out here on Equipment World.
Ergodyne Chill-Its 6609 Hard Hat Liner Sweatband, Terry Cloth
Milwaukee Workskin Warm Weather Hard Hat Liner 425G - The Home Depot
Bison Life Sweatband for Bump Cap/Hard Hat (Pack of 12)
ACERPAL Cap Style Hard Hat, OSHA Safety Helmet, Custom Black Solid
Safe Handler Replacement Sweat Band for Hard Hat or Bump Cap 60
NoSweat® Liners for Hats, Visors, Helmets, and Hard Hats
NoSweat® Performance Hard Hat Liners
Mobestech Hard Hat Lining Cloth Accessories Hard Hat Liner Insert
Ergodyne Chill-Its 6609 Hard Hat Liner Sweatband, Terry Cloth