I have got my hands on a bottle of Nioxin Scalp Renew ($13 for 2.7oz) and will pass it on to reader who sends in a comment telling us why you'd like it. You also have to promise to write a review (it can be short and painless for those of you who are not natural scribes).

Nioxin Scalp Renew is billed as an anti-aging dermabrasian treatment for the hair. The theory behind it,is that gunk builds up on the scalp
preventing topical products that stimulate hair growth to penetrate and do any good. Nioxin used the kind of exfoliation ingredients that turn up in facial products: enzymes, alpha and beta hydroxy acids and willow bark to rid your head of unwanted debris. Scalp Renew is said to increase cell renewal by 38%.

Note: this is a single-use monthly treatment.