Thumbs up for turmeric! This recipe with ginger and mustard and curry looks good to me as well.
I have medium brown hair, I used to use turmeric to give a gentle golden hue to my brown hair. It's hard to see the difference when I'm not in the sun, but it really gives my hair more gold in the sun. I love it and am thinking of dying it again for summer.
People on the net are always saying how the turmeric washes out so fast... Mine doesn't, the coppery colour from dying it last year is still in the tips of my hair. I should probably attribute this to me using a "no-poo method" where I only use water unless it needs a deep clean when I use baking soda and a vinegar rinse.