This lampshade is made from 16 triangular cardboard panels connected by coloured folded paper. The Triangles are held in place by a circular hinge, and are free to rotate about the hinge thereby easily changing the shape of the lampshade from uplight to downlight.
I've used 1.5mm cardboard for the structure and triangular panels, and standard pink A3 paper for the ambient colour - i was going for a warm look, but playing around with the colours could be interesting.
I'm planning on developing this lampshade, there's a couple of problems with the design as it is, but the overall effect is pleasant, and the usability of the uplight/downlight works well. I made the lamp about 5 months ago, but the photos show its recent condition.
Currently i'm using a pink string to hold the lampshade in place at either extreme, but that's a stop-gap solution i hope to rectify.
If you'd like some more info, please feel free to ask. Once i've worked up the design better i'll consider adding a step by step.
It was a fun project, probably took about 4 hours to cut everything out by hand and assemble once i'd got the design work sorted. Should retrofit onto most lightbulbs.