Fabric makes a brake light for bikes, using a motion sensor.
 

The new Fabric FLR 30 makes clever use of an accelerometer to increase brightness as speed falls. This results in a dual-purpose light that alerts traffic when you intend to slow down or stop. Compact, reliable & USB rechargeable. Designed to be mounted in multiple positions.

Width: 23mm
Length: 74mm
IPX5 water proof rating
Tough waterproof nylon case
Universal mount with rubber strap

Fabric | FLR30

http://fabric.cc/wp-content/uploads/...ro-desktop.jpg

Interesting, but with the relatively low output of the Fabric tail and headlights, compared with other makers, it seems like they're catering to the cosmetic conscious folks who only occasionally need lights and prefer form over function.

Funny run times:

• Full power: 8 hours
• Medium power: 9 hours

:foo:

Yeah, 30 lumens? Not at all daylight visible. You could probably see it in daylight but it wouldn't be obvious. Brake lights need to be attention grabbing. I'd say 60 lumens going up to 120 would be good tail/brake lights. This seems pretty weak. At least it's cheap, but if it doesn't work very well it doesn't particularly matter how cheap it is.

Do you think drivers would understand what it's trying to communicate?

I don't think getting brighter as you go slower is going to make a difference to driver. Changing or starting pulsing will. Priority lights were designed to pulse for several (5?) seconds when the brakes were applied on a motorcycle and they used to attract so much attention when I used them that people would give me plenty of room. They didn't know what was going on, and didn't want to get to close to it.

Good point! :foo: for myself, I always use the flashing mode instead of the constant one cause I think flashing is more attention-grabbing.

Well, on the plus side, the accelerometer should make it a full time strobe in chipseal country.

Yeah, it should be interesting for a lot of us who ride on streets with traffic. I think mine would be strobing most of the time.

Lupine has had the same feature on their taillight for several years now. And it's a high bright light (160 lumens, if memory serves).

J.