Turning tarpit
A turning tarpit is a form of Turing tarpit in which there is a sequence of commands, modeled as a rotating wheel. In a turning tarpit, language commands do not directly manipulate data, but instead affect the command wheel(s), by changing their rotation or executing the current command.
Overview of the Genre
The earliest example of a turning tarpit in the world of esoteric programming languages is probably reMorse (1998). Whirl (2004) embraces the technique most explicitly, styling itself as "dizzy programming". Fortuna (2005 or earlier) is probably the first turning tarpit to use the image of a wheel. Wunnel (2011) applies the turning tarpit technique to the problem of designing a 1L, and expands on the idea by using a two-dimensional torus of instructions instead of a one-dimensional wheel. Braincrash (2011) is a brainfuck equivalent. Jolverine (2012) is a conscious attempt to expand the turning tarpit genre by introducing a new feature: modifying the order of instructions on the wheel during execution.