Here's a basic filament holder anyone can use. It's fitted for Makerbot filament spools but can hold and filament that fits within the base. The rod fits easily through your filament spool and is placed on the base in the slots on top so it can turn freely. There is a filament guide piece that fits into the base to keep the filament flowing perfectly. I made this design over the past couple of days using tinker-cad. You can print all three parts at once or individually. The spool rod features the Makerbot logo and the base and guide bar are customizable to feature any design or pattern you want to make it your own. Added a new version where the sides of the base are thinner.