Today I discovered a place describing this method to generate some beautiful (though kind of random) pictures. Some serious danger for your camera is involved ... but some pictures are indeed worth it.
One of my favorites is this http://www.flickr.com/photos/mihaitza/392479098/, but many more can be found in the links below, e.g. at http://cameratoss.blogspot.com/2007/02/clickykbds-picks-issue-24.html.
Links: The cameratoss.blogspot with a mini-howto. Lots of pictures at https://www.flickr.com/groups/cameratoss/pool/.