Thanks for your input. For those who found my inquiry silly let me further clarify my intention: for medical reasons I am looking for drugs that specifically enhance pleasure experienced at some level already without the drug. Say you listen to music, have an orgasm, take a look at an amazing scenery - all these induce pleasure for a healthy individual without any drugs administrated. So what drugs specifically enhance this pleasure? In other words:
What drugs multiply pleasure?
Like I said, I do not consider opioids to be such, as they merely add pleasure, not multiply it. You can be alone in a dark room with zero pleasurable stimuli and still get pleasure from opioids. That's because they add pleasure, not multiply the pleasure you experience. This is easily seen in their pharmacological profile as well.
According to this thread stimulants are the number one choice. Too bad my brain doesn't agree with them.
Cannabis and psychedelics seem to be getting votes too. I feel that psychedelics at high doses are too psychedelic to be pleasurable -they're interesting, but not pleasurable. What do you think?
I would be really interested in how GHB does the job. People say it's a wonderful aphrodisiac and social disinhibitor but I also hear it makes things like listening to music etc. more pleasurable. Sounds promising.
E: In terms of various activities (chores, hobbies etc.) no pleasure enhancement is needed, just motivation enhancement. That's not what I'm looking for. Stims surely do both though.