Summary

Apparently I'm not the only one who thinks $160 is a bit much for a plastic box. This is a gelbox designed for the Cooper Union iGEM team. It can run up to 30 samples simultaneously and is made from lasercut panels.
BOM:
6mm and 2mm acrylic sheet
20x20mm acrylic square rod
2 Male/Female Banana plugs (or the standardized plug in your lab)
Platinum wire (AWG 30)
Four M3x15 screws and nuts
Acrylic glue

Instructions

1) Cut the following plates:
6mm sheet

Two “Sides”
One “base_plate”
Two “electrode_plate”
Two “front_back”
One “lid_top”
One “lid_electrode”
One “gel_base”
2mm sheet
Two “Comb”
Two 20x20x190mm acrylic square rods

1) Laser cut specified parts
2) Glue all plates, except the “electrode_plate”, together using acrylic glue. Clamps are recommended to ensure a watertight seal and better alignment.
3) Attach male banana plugs to holes in the “sides” plate
4) Attach the electrode wire to the power plugs and thread through the small hole in the “electrode_plate” so that the small hole is on the opposite side of the power plugs and the wire is behind the grate section
5) Screw both “electrode_plate” pieces to their respective sides using M3 screws
6) Notch two evenly spaced slots into the acrylic square rods, this will be where the combs sit. The notch depth depends on your gel thickness but should be around 9mm
7) Glue the square rods to the “gel_base” using the combs as alignment references
8) Glue lid pieces together and attach female banana plug

DIY Midi Gelbox