In article , Mark T
lid
says...
Bottle dynamos - all they do is suck power and make a funny noise. Today I
saw a reverse bottle dynamo; one that ADDS power. The working mechanism
sits stealthily over the front wheel - might be good for the peeps worried
about their TT times

www.flickr.com/photos/86862441@N00

Not odd at all, just a French moped. Apparently you can still buy them:
http://www.bullnet.co.uk/shops/test/velosole.htm