It's been with me for many years. Paul Mitchell's Tea Tree shampoo.
Now this one is not just some eucalyptus tea tree useless mix, this is really strong minty tea tree that makes your head feel like your tongue when eating a mint.
It's great. It refreshes in the morning, is excellent to finish off a long day in the office or is also great when you have a headache. Massage in 3 times and you will be completely recovered.