The idea for these shelves came to me a few years ago, when my girlfriend fell off a bicycle and broke her arm, resulting in her having to wear an Ilizarov device. They are stupid easy to make/modfy/disassemble, and look good :)

Supplies

14 MDF planks (800 x 200 x 20 mm)

12 threaded rods, 6 connectors, 168 nuts `(10 mm diameter)

Tools

Power drilll, with a 10 mm wood bit

Tape measure

A formula for the number of nuts:
(# of shelves x 4 (holes) x 3 ) - 4 (when a connector is placed under the shelf)

Step 1: Measure, Drill, Assemble

Measure a line at least 25 mm from each edge of a shelf (or use a >= 25 mm wide paint tape), in order to make sure there is enough space for drilling holes. Drilling MDF is easy, just make sure you don't break off the tip of the board. I assembled the shelves in two interconnected columns and anchored them to the radiator pipes