Apparently Pretzels Getzein had a pretty odd curveball back in the 1800s. From Wikipedia:
During his career, Getzien drew acclaim for his curveball. Getzien's version of the pitch was sometimes referred to as the "pretzel curve."[5][8]Sporting Life described Getzien's unusual delivery as follows: "In delivering his 'pretzels' 'Getz' faces third base with one foot in either corner of the lower end of the box. Bending the left knee slightly, he draws his right arm well back. Then, straightening up quickly, he slides the left foot forward with a characteristic little skip, and, bringing his arm around with a swift overhand swing, drives the ball in at a lively pace."