1 x piece of paper, maybe 1/2 inch of a couple of the grey Caran D'Ache pencils (have to keep the points sharp). Next to bugger all, really. I was bored on a synchrotron trip between starting measurements and managed to get a few drawings done.
(
Colonel Boris "...a desperate Buzzfeed imitation...",
Mon 13 Jun 2011, 11:38,
archived)