Analyzing Stimpak's properties from all games means it is a drug that is able to speed up the process of cell and tissue regeneration while simultaneously being able to limit the process so that it doesn't go beyond the natural physiologic and anatomic properties of the organism, without causing a significant strain to the body's metabolism rate and without any side-effects. Extrapolated a bit, it can be used to heal almost any trauma instantaneously and can greatly help with most if not all forms of neoplasms, with little or no risk involved. Extrapolated even further, it could help with "regrowing" lost limbs etc. So panacea, basically, or at least a basis of one. Not a drug I'd try, but one I'd love to keep handy. Other than that, Mentats. And Nuka Cola, I guess.