off-topic: If you like reading about the historical use of the coca leaf, opium, tea, tobacco, khat, coffee, etc, I really recommend the 1855 book "Plant Intoxi

off-topic: If you like reading about the historical use of the coca leaf, opium, tea, tobacco, khat, coffee, etc, I really recommend the 1855 book "Plant Intoxicants". The book describes both historical and contemporary usage, but owing to its publication date it's all historical now.