Not sure I see this as particularly useful, but kind of cool, if a little over the top on the technology used...
http://gizmodo.com/5991284/hacked-bike-headlight-projects-your-speed-on-the-road-ahead
I think swap the projector for frickin lasers and it'd be better (although negates using it as a headlight).
@CasaSteve started
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Not sure I see this as particularly useful, but kind of cool, if a little over the top on the technology used...
http://gizmodo.com/5991284/hacked-bike-headlight-projects-your-speed-on-the-road-ahead
I think swap the projector for frickin lasers and it'd be better (although negates using it as a headlight).