I'm in South America right now. About 10 days ago I was in Patagonia - in Torres del Paine national park where we experienced a brocken spectre one morning (see below):

The Paine massif - a mountain range that is around 9,000 feet high, rising out of the patagonian steppe, was shrouded in cloud one morning. We saw the outline of the mountain projected onto the foreground cloud from the sun behind the mountain range. What you are seeing here - is a 9,000 feet shadow cast onto a band of cloud between us and the sun. It was quite spectacular and I've never seen anything like it before.

Many thanks to Clive Maidment for sending me the iPhone picture.