^ that's everyone's favorite- no one includes it because it's just so friggin obvious. This is really a "what's your second favorite next to ether+glue or jenkem" thread.
I'd go with any short acting opiate besides fentanyl, seconded by a short-lasting psychedelic. Huge fan of 4-ho-dipt, oral salvia and smoked DMT.
less favorite: kratom, (now that my tolerance is low) suboxone, oral stims and weed.
and who doesn't have a soft spot for n2o