Full Function Dynamo Light for Around $20

One way to get a full function dynamo light, with a proper beam pattern,
is to use a Schotty-diode bridge rectifier and DC-DC converter to drive
a rechargeable light.

I just received such a light from Amazon. I tried operating it with no
battery, from a 500mA DC source (at a wide voltage range), and it works
fine.

Current consumption is as follows:

500mA high (I'd estimate that it's 350 lumens, advertised at 500 lumens)
140mA low
270mA flash

I am going to use a DC-DC buck-boost converter to provide a constant
voltage from the dynamo. The dynamo limits the current output by design
so I don't need to use a constant current converter. The light output is
less without the battery, but still superior to most dynamo lamps. With
the battery charged that light output is much better than all but the
most expensive dynamo lamps. The spot to flood capability is very useful.

I can already anticipate one person turning red and screaming “cheap
Chinese flashlight,” but the reality is that this is a much better
system in terms of functionality, output, build quality, beam pattern,
and cost, than any sub-$100 dynamo light on the market. Is it as good as
a $200 Supernova E3 Pro 2? No, though it does have the advantage of a
daytime flash mode and being able to be used as a repair light. You can
charge the battery from the dynamo (with the light off) or charge it
from the mains. You won't ever be left in the dark with a dead battery
because it will work off of a dyno with no battery at all. With six
bicycles with dynamo wheels I'm not going to be buying five SuperNova E3
Pro 2 lights.

When I have it hooked up to the dynamo in a couple of weeks I'll give
another report.

The Amazon link is http://www.amazon.com/dp/B008261UOO. I ordered it
from the vendor offering Amazon Prime shipping and it came the next day.

OK how bout a multiple color blinkie set for attachment to a vest ?