While I'm giving love to Bumble and Bumble...
I'd been hearing about Bumble and Bumble's Hair Powder for years. I believe they recently re-formulated the product, and gave it new packaging to boot. I finally decided to try it after my friend (and Jack & Hill tester) Kelly told me about her experience with it. She actually ended up taking hers back to the salon for a refund, because the product was just way too messy for her, as she runs her fingers through her hair all day. Because this powder will turn your fingers and hands brown with the merest touch, that is for sure. "HI, here's $37. Please muck me up." (No, it's not cheap.)
For me, the mess is not such a big deal - I only spray the product on my roots (and shake off any excess after it has dried), and if I touch my hair, it's usually to brush it out of my face. Rest assured, though: You will need to wash your hair before you go to bed, or you'll end up with brown stains on your pillowcases. (Or just use old pillowcases.)
So it's expensive and potentially very messy. That said, I love it. I usually need to wash my hair every day if I don't want to look like a big greaseball, but this stuff lets me go one more day without assaulting my hair with shampoo and heat styling. (I find this particularly worthwhile after I've paid to have my hair professionally blow-dried and styled.) It just absorbs every jot of oil and infuses hair with amazing volume. The important things to remember are not to use too much, unless you want people to notice the powder, and to let the product dry before you try styling your hair. Oh, and put your makeup on after you've used the hair powder - that way, you can brush away any brown 'dust' or smudges before your makeup goes on.