By the mid-20s, men will know their back hair destiny: barely there, a few tufts, or full and bushy. Is yours a magnet for women? Or a throwback to the Stone Age? If you want to tame the shag, laser hair removal can thin back hair or remove it all, and the results are nearly permanent. Cheaper options include waxing, hair removal creams, and razors, with results that last up to a few weeks.