I have had really good experience with the Blackburn Quadrant/Mars combo.
I've used a few different brands and these seem better than lots others, they seem to take a bit of a beating, don't drain batteries too terribly quickly (yet are bright) and the taillight has great side indicators.
I'd give you a link but I haven't been a user for more than one full day, so I can't put up links yet. A search for "blackburn" should turn it up.
I've tried so many different lights that I'm getting headlight poor. Most of them don't throw out enough light for me and if they do the batteries don't last, but the reviews on this one look pretty good. I know LED's are getting better...maybe this one is bright enough. The combo (tail light/headlight) is only $17 at Amazon so I might give it a try. Do you think it's bright enough for speeds of around 20-25 mph?
I just buy a pair of driving lights at your local auto parts store keep one as 12volt and run it off a rechargeable battery. The other I modify with a $1.59 E10 lamp socket from Radio Shack. Stick in the bulb from the Schwinn generator light set and you have a high and a low beam in matching housings. You can do the same with tail lights too, but you can put both in the same housing since taillights don't require specific placement in relationship to a reflector.
Has anyone rigged a tail light slash brake light, Im in Las Vegas and they treat it as a Moped as far as I can tell. They want a tail light that will illuminate while breaking visible for 200 ft in daylight. I can probably get away with no turn signals but I have to rig something for the front and back
have a look at this...i know it seems hokey, but it's only hokey until it's been installed the way you want & it's doing the job. i'd think the brakelight "switch" could be used in a diy system if that's the way you'd rather go.