I really liked the design of MarB & Theo's holder but what I didn't like was that it sat flat and occupied a lot of cells. Now, it stands vertically, has been shortened so it wont topple easily, and only takes up 2 cells. I may redesign it in the future so tweasers are less likely to fall forward but so far I haven't had that issue.

Prints vertically with or without supports, does not need much infill (10-20% at most) as its mostly made of walls. 

I have included a .step file for easy modification to the design. I encourage others to modify it to suit their needs.