Meet the hemihelix!
Observed by a group of researchers at Harvard, a hemihelix occurs when a corkscrewing shape changes the direction of its spiraling. These locations are called perversions (giggity) and look like the part of the spiral being pointed at by the arrow:
(Piccy from link above)
The Harvard team observed the hemihelices when they were taking two strips of rubber of different length and stretching the shorter one to match the length of the longer one before binding them together. Unexpectedly, the hemihelix shape appeared when the tension on the joined rubber strips was released.
Understanding how and why such shapes are formed might help researchers mimic the shapes of molecules that could be used in nanotechnology. Says Dr. Katia Bertoldi, associate professor of applied math at Harvard, “Once you are able to fabricate these complex shapes and control them, the next step will be to see if they have unusual properties; for example, to look at their effect on the propagation of light.”