This site is AWESOME. I have naturally dark-golden blonde hair... I have some natural reddish tones in my hair, and when I highlight with henna(I have done entirely henna-red) I get SOOOO many compliments. Henna takes you natural color and does some amazing things with it. A huge bonus... If you highlight(my sis is a professional stylist, and i have her foil it in like commercial color) using henna, as it grows out it looks far more natural than commercial color. Henna fades over time, but not in a yucky washed out blah kind of way. I could go on and on and on. I LOVE this stuff. Anyway, if you go the Mixes page on the HFH website and look for Chrissy in the second column... That's me! Used to be they gave away free henna if you submitted your mix and a picture. This was back when I did my full head in henna. I did it a few(maybe three?) times more after this first one, and ended up with some really intense red... Very typical rich carroty wildness in the sunshine and almost Jessica Rabbit red in indoor lighting. My hair grows so fast, I'd have roots pretty quick(wouldn't have been an issue if I'd only hennaed once) so eventually went to highlighting. Everyone thought it was my natural color. Maybe if I get some time I'll try to link to some pictures after the multiple applications.
Hope that works. Link to my henna hair! Unfortunately, I don't seem to have any pictures that really show how the highlighting works... In photos it seems to just blend in. Rest assured that it's really cool though.
ETA: The picture in the black sweater is from my first application. The other three are after what was probably the third application. You can see how dark it look in the indoor pic.