While coming back from a transfer to Great Ormond Street Hospital (GOSH) I came across a piece of art called "What the eye can't see the heart can't grieve for", of which you can read more about on this website.
It is basically a number of photographer's flashguns connected to geiger counters, which makes the flashes (which are spread around a couple of buildings) activate randomly. Interesting and pretty, which is only ruined by the pretentious twaddle on the artists web-page.