Created the diamond file set holder for my desk at work... then got home and realized my needle file set was similar, but there are 12 files, not just 10. So, opened up the design and adjusted for the set of 12. Same design as the other, can be printed as just the holder or as a "lazy susan" design using either airsoft BBs or 1/4" ball bearings. Won't turn terribly smoothly unless your printer does really nice work.
Still has provision for a Sharpie or Inexacto knife (or standard large Xacto knife) in the center.
Included the F3D file if you've got a similar set of files and need to make similar modifications.