Here are some 3D printer accessories and modifications I couldn’t live without.
1. Hot end cooling fan.
2. Hot end cooling fan shroud.
3. Bead cooling fan.
4. Bead cooling fan bracket.
5. Remove D1 so that the Arduino does not receive harmonic distortion from the stepper motors and heating loads.
6. Electronics Enclosure.
7. Electronics Cooling.
8. Bed Lighting.
9. Lighting and fan control.
10. Power Switch.
11. Stepper motor wiring harnesses.
12. Stepper motor wire bracket.
13. Aluminum print surface.
14. Heated print bed.
15. Filament Spool Holder.
16. Extruder and adjustment.
17. Cheaper rail system.
Most things can be downloaded here: http://www.thingiverse.com/electronhacks/designs