Building on the astounding * level of success of my last post here on HB, of a method to sneak a gingerbread house, with a very large oven, near a children's play area, through the planning permission system (and who amongst us hasn't tried that once in their lives?) I decided to try something else.
rigid container, capable of maintaining a hard vacuum, with a toroidal magnetic containment vessel (like one of them makatoks) inside , with iron filings, simply because they are magnetic and cheap. The iron filings are then accelerated up to near light speed and, people can try and turn it.
It could also be used as some kind of novelty pest control, with sufficient control over the magnets, one iron filing particle could be allowed to slip the vessel and et voila, the fly is no more - in a flash as the kinetic energy is transformed into heat, light and sound.
Admittedly if the fly was inflight you wouldn't get the proper mushroom cloud effect, so it might be better to wait for the fly to land first.
The kit would also include ear protectors, a dark visor and some kind of self-adhesive patches to cover over where the iron punched through the side of the vessel.