Low dose LSD has interesting potential. Low enough dose to not induce psychedelic effects. Plenty of reading available on it if you google.
I've tried a quarter of a 150ug tab which just made me feel great, a third was getting into psychedelic territory.
From my experimentation with a third, it massively enhanced my pattern recognition, I was looking at geometric trippy patterns and if I focused on a particular shape say a triangle, then all the triangles in the picture would appear to just pop out at me, likewise with a square etc. That's an obvious example, but I'm sure it has the same effect on other mental thoughts. Unfortunately a third was getting too trippy for me to focus on anything. A quarter is probably a safer dose.
I'm quite sure that's what LSD does to your visual cortex, it's like now if you look up at a cloud your mind will try and find a pattern in it, then you say 'oh it looks like a WF member coning himself'. LSD increases that massively (depending on your dosage). If you go far enough with the dosage, like I did when I first tried it... I saw ancient aztec carvings in the woodgrain pattern of my floorboards. That's too far to be useful unless you're an artist or something. If you're trying to find a pattern in your shitty 'you won't believe what this 5th grader makes a week' ads or make obscure connections between thoughts, a sub-perceptual dose could be an interesting boost.