If you used speed, it would have to be methamphetamine and not amphetamine. (you guys can look up why, would have to do with amphetamine freebase sucking the cock). And that is a turn off for most people.

I've heard of this being done with mescaline, I don't know if it's true.

LSD and Psilocybin break down in high temperatures I believe, so again shit.

I didn't know you could smoke MDMA? But I suppose if you could it might work.

You could try throwing some heroin into it.. works when smoked.

But again, this is all theory, until we find someone willing to experiment throwing some of their money away to see if the plant 1) even absorbs the chemicals and 2) distributes the chemicals into the buds and isn't absorbed by the leafs or stems and such..
then iuno wat to say.

yeah it wont work, the shit needs to be broken down to be sucked up to the plants roots, so basicly your breaking down the fairly unstable amphetamine molecule in order to get it to go in to the plant, you would be better off sprinkling the shit on top of a bowl...remember chewy's