This pencil organizer that's also a giant functional nut and bolt – size M80, to be exact.
Interior dimensions: 69mm (diameter) x 107mm (height)
External dimensions (WxDxH): 100mm x 114mm x 110mm
I found that this was a nice size, both visually and practically.
This is also available on Thingiverse and on Printables.
No supports required!
For the nut, the default (organizer-nut.stl), the threads have a 0.3 mm tolerance, which works great on my Prusa MK3S. I recommend starting with this. If your printer doesn't print with tight tolerances, there is an alternative with 0.5 mm tolerance, called organizer-nut-looser.stl.