Red Bull is pretty good stuff.. I took some one afternoon and I felt great for quite awhile, then I woke up in the middle of the night and was eating everthing in the refrigerator....
Kratom leaf is legal and highly addictive, it used to be cheap but that was then... I used to grind that up and eat it and dang, I was putting in long hours writing software and loving it... the code came out ok too... if it's physical energy you want then you just want health basically and that takes a while with good supplements and exercise and all ... our ancestors had a lot more physical work to do and they had a much better food supply.. they averaged 10,000 calories a day and were not fat, typically they had hard bodies really until they got old then got skinny but they were still happy I guess...