Lasers have recently come into use in hair restoration. A laser is used to encourage blood flow around existing follicles. However, there are some that say the method doesn't really work, and even in the best-case scenarios the results are less than spectacular.
Effective hair restoration is a big deal, so don't expect it to be cheap. Hair restoration doesn't come in a can or a poultice, no matter what anyone says -- it's generally a lengthy and expensive procedure accomplished through surgery or careful cosmetic work.