In Arlington, BikeArlington and a number of great volunteers (many from this forum, THANKS!) have done a light giveaway in which we have distributed free sets of lights along with safety literature.
Check out a few write-ups here:
http://www.commuterpageblog.com/2010/12/lights-for-bikes-2010.html
http://www.commuterpageblog.com/2010/10/lights-for-bikes-day-laborers-edition.html
I think other jurisdictions have similar programs too.
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