I drink a lot of dandelion tea. I also drink a lot of nettle tea, mainly because I think that it makes my hair grow faster. I don't like the taste of nettle tea (it reminds me of the taste of cows milk) so I add peppermint tea to it. The peppermint manages to overpower the taste of the nettles.

There was a time when I was using herbal rinses on my hair and I found that drenching my scalp with nettle tea then massaging it helped to shift grease. It wasn't quite as good as shampoo but it was the next best thing.