Basically any of those. Even low-doze nicotine lozenges and gum (I quit smoking many years ago and switched to vaping, and quit that a couple years ago).
That is pretty cool, I didn't know that even nicotine could, as a stimulate, help people feel sharper or concentrate better and make their efficiency increase. Are there particular types of tasks that stimulants, even nicotine, seem to help with more than others? It might be too private, but I ask all sorts of people since I like to learn a lot about these things in detail and get the inside scoop about their real effects and how people feel and what they go through on them, but have you used a variety of different sort of drugs (I also ask people because I have no personal direct experience taking drugs except some things while in the hospital mainly, and besides that my exposure is through asking questions of people and the reports from my medical doctor mother dealing with various patients since Hawaii is full of drug users of all sorts, so I get to hear stories about users and what its doing to them and also their families and all that)? Like, cocaine, meth amphetamines, then there are weirder ones that came out later and sort of after my time which I haven't spoken to people using them, like weird names I heard coming out of Florida or something.
I got to hear about cocaine from some people, but I hear everyone's personal stories if I can to see the similarities and differences. I've also found out about psych medicines and some of them which seemed to cause people terrifying memory lapses and gaps, and also got to watch them on the drugs, interacting with me, and how it seemed to alter personality, alter decisions (sometimes making extremely dangerous or insane seeming decisions while in the dream-like detached influence of the drug seemingly). I forgot some of the names though. My father was always smoking and drinking caffeine (I think he still drinks caffeine) all my growing up years, and my sister seemed to be pretty dependent on caffeine, and also took ephedra for a while. Everything has an effect though, normal salt, soy lecithin also effects the mood and mood chemicals (more notably in males probably since they might not be used to the estrogenic type effects or influence on the thyroid).
Anyway, if you or anyone else would like to list all the drugs you've ever taken and how they effected you and what they are good for and why they might be not good or bad sometimes or the risks or side effects experienced, that could be really informative.
I also heard a lot about various club drugs and hallucinogens, from various people including a friend of mine who was in contact with a big time drug user who became their dealer as well, and used the drugs initially to basically drug and rape my friend, even though they don't consider it a rape really, even though I'm pretty certain putting in drugs in someone's drink that leads to them becoming totally drugged and basically incapacitated and then immediately proceeding to touching them and having sex with them while they were in this state, is pretty much totally rape. Drugs are used in a lot of messed up sex cases or crimes. They had saved the guy (based on me telling them to) from a drug overdose and suicide attempt, and so then this guy invited her over to thank them for saving his life (she hadn't known him very well or anything, but watched him basically overdose online and I told her to find out somehow how to save him and a mutual contact in the UK was used to get the police over there somehow, it was really difficult but saved his life). Anyway, then she got all these various drugs that he kept basically testing on her, and I tried to convince her to get away from him, he mailed over cocaine dangerous even after they separated out, and then he finally died by falling and hitting his head (while on drugs no doubt), and I was quite pleased since he was a freaking menace.
That is why I really don't feel too bad when they say tons and tons of drug users are basically dying off all across Canada. I had one totally messed up guy fall on me really hard and I couldn't even lift him up in case he had needles somewhere on his body or pockets and could get poked and diseased for life. I actually really despise drug dealers and their addict slaves who I've seen making a mess of everything wherever they seem to be, and terrorizing beautiful Hawaii and terrorizing Canada. I would look out the window in my neighborhood in Canada and month after month it was getting worse and nothing was being done, in the middle of the night some guy was walking like a zombie down the road, others broke into my apartment building smashing the glass door after yanking on it for like an hour, only to fart inside the building after being unable to break into some old man's apartment. The more I think about it, the more I think about how much trauma and fear these drug users have caused, harm to themselves and others or just chaos by being erratic and out of control, and how much I really genuinely hate them and wish they would stop or just die off or something.