You can buy amber lights. I've used one on the front corner of my bike trailer, most useful when riding on bike paths at night, at least that was the thought.

I don't think there would be any reason to use amber (or white) on the rear.

There are a number of day lights and rechargeable lights on the market, as well as lights taking any size imaginable of battery.

I dislike the idea of using daylight taillight at full power after dark. They are just too bright, and I believe the effect of blinding may in fact be worse than not being seen.

There has been research on turning towards lights, and I believe it is worse when the rider/driver is blinded.