Super Simple Isosceles Triangle Unit (SSIT)
This is a very simple unit which can be use for all sorts of spiked polyhedra. The spikes can point both outwards and inwards of the model.
It was designed independently by many people. I’m using the name that Meenakshi Mukerji used for her version since it is through her site that I learned about the unit. An older document indicates earlier discovery by Roberto Morassi and Jeannine Mosely.