This topic came up at the Bangor event. I've never actually seen one, but since they are caused by satellites, (and you need lat/long to predict/view one), I thouht I'd mention it here.

Here is a link to a site that predicts (among other cool things, like the postion of the ISS) where (and when) Iridium Flares will occur. I'd like to hear from folks who've actually seen one.