The knuckleball and slurve are probably the weirdest pitches we have most recently heard of, but there is a list of “weird” baseball pitches out there, maybe a quite arbitrary one, which shows that there have been some real weirdo’s. Add to that a weird pitching stance or just a weird guy in general, and you got yourself some mystique and a possible cult guy, like Zack Greinke.
Zack Greinke has thrown some really slow pitches, with a logical big drop, but I guess a real avid baseball writer (in other words: not someone like me) would have trouble calling his slow pitches an “eephus”.