I’ve seen a few mentions recently about the Tigra BikeCharge, an all-in-one plastic contraption that combines a dynamo with cheap lights (front and rear) and a USB charging port for your mobile electronic devices.
I personally don’t think the device charging aspect is especially interesting, but the mounting method looks intriguing. The “gearbox” shown in the diagram fits between the fork end and spokes. It’s not shown in the diagram, but a “clutch” — a little plastic tab — engages the gear box to one of the spokes, so when the wheel turns, the gearbox turns and generates power. You can see this a little better in the installation video below.
London Cyclist sells the Tigra BikeCharge at his online store and says it works as advertised. The install method is a clever hack that seems much easier than installing a sidewall bottle dynamo or a hub dynamo. In the USA, the identical twin rebadged as ECOXPOWER is available from Amazon; Amazon Prime is available for the Ecoxpower dynamo.
Disclosure: If you buy by clicking through the Amazon link, I get a buck or two from that sale.