Do you like gears? You'll like this one twice as much, since it's a double helical gear, also known as a herringbone gear. Print two of them, and flip one over. You'll notice that they mesh perfectly, and have the side benefit of self-aligning; there's no thrust produced by these gears. You can print the attached base if you want to make a toy of sorts out of it.
I printed numerous versions of this out of white and black PLA at 220 degrees, with no support. The top and bottom corners of the gear are rounded, but the angle isn't enough to need any sort of support. Since it's got very small details I would recommend a .1 slice thickness at maximum, and ideally you should print with some sort of active cooling.
This was created in AutoDesk Inventor Professional 2016, imported to AutoCad 2015, and modified to create the herringbone design and hole.