I came with this tetrahedron while learning the basics of Fusion 360. Supports were quite hard to remove, but I'm happy with the results.

Could be used as a sturdy painters pyramid or as keychain. If you need modifications or have any ideas concerning the model, let me know.

The GCODE is only 30mm for test and has variable layer height and supports, printed with Prusa MK4 and 0.15mm speed mode.