Naked Singularity
Naked Singularity is a classic by Daniel Scott. It is basically a combination of Rotisserie transitions with Reverse Bird. It may be the most well-known symmetrical machine.
A video:
The name Naked Singularity refers to a situation in Physics where it would be possible to observe singularities. Naked Singularities have not been found and may be impossible - while singularities exist, they are "dressed" by event horizons.
I have created some more machines using Rotisseries analogously, and include Singularity in their names. One of them is the Dressed Singularity.
I base the Naked Singularity often as a preparation for other machines like the Nataraj.
Another video, with Niki:
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