I have long straight fine-thin hair, does any1 know of any natural hair thickening remedy?

Use a "kitchen" conditioner. One of the best conditioners for those with thin hair is white vinegar--that's right, the same kind you use in cooking. Mix one tablespoon of white kitchen vinegar in a pint of water and massage it into your hair after shampooing. It changes the chemical balance of your hair to be slightly more acidic; for some reason, that makes hair appear thicker and gives it more shine. The vinegar doesn't leave an odor in your hair.(But of course, be sure to rinse it out before you step from the shower.)

Or, be an egghead. Another kitchen item that can contribute to thicker hair is the lowly egg. Simply crack an egg over your hair before shampooing, and toss away the shell. Massage it in for five minutes and then rinse it out. Since egg is basically animal protein (albeit nonhydrolyzed), it has the same effect as the specially formulated shampoos.

I have also heard that rinsing with beer works. Once a month use a can of flat beer after shampooing. Choose a beer that does not have a strong odor. Shampoo and rinse hair as usual. Pour the flat warm beer on your hair and work it through. Rinse with lukewarm, not hot, water.

I have long straight fine-thin hair, does any1 know of any natural hair thickening remedy?

I think Herbal essences has a shampoo and conditioner in their new line that volumizes hair