OK - this is either a rubbish idea, or no-one's actually thought of it yet, but how about a pair of cycling gloves with a set of orange leds in an arrow shape on the back, and a set of contacts in the palm, the idea being that when you're not touching anything (ie the handlebars) the LEDs flash, so that you have a nice bright signal when you stick your arm out?
<edit> Looks like someone has something similar on the market already
http://www.expertverdict.com/ProductDetails.aspx?language=en-GB&product=1124596 - there goes my moneymaker
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<edit> Looks like someone has something similar on the market already

