i have made a atat chestlight.here are some pics.the switching time is 13-15 seconds:
http://sphotos-a.ak.fbcdn.net/hphoto...62230861_n.jpg
http://sphotos-b.ak.fbcdn.net/hphoto...25960947_n.jpg
http://sphotos-d.ak.fbcdn.net/hphoto...99159362_n.jpg
http://sphotos-g.ak.fbcdn.net/hphoto...51990679_n.jpg
http://sphotos-a.ak.fbcdn.net/hphoto...62230861_n.jpg
http://sphotos-b.ak.fbcdn.net/hphoto...25960947_n.jpg
http://sphotos-d.ak.fbcdn.net/hphoto...99159362_n.jpg
http://sphotos-g.ak.fbcdn.net/hphoto...51990679_n.jpg