I read somewhere that in the early part of the 20th century they made men's toupees with bases of hair lace - a netting actually made with human hair. They were supposedly excellent, but too expensive to be viable for most people. John D Rockefeller wore one.

The big breakthrough came when Max Factor developed the lace toupee for Hollywood actors in the 1950s. I guess his lace was pretty similar to what you can get nowadays from a company like Toplace - some sort of manmade fiber.