1. las psyclepath said, lights and reflective gear are the key. As a slow Randonuesse, I know these things
2. Front lights: wish I had the money for a dynohub, but I've got two Cateye El-500's: they were about $30/each, and I can get a month out of the batterys(Almost all of my weekday riding is in the dark ) so , you can get buy without spending a ton.

I know i',m going to get some post about what "junky" lights they are, but they seem to work fine for me. I've actually gotten sincere comment about the amount of light I have
I also have a Princeton Tec headling on helmet. Handy for reading cue sheet and 'puters on those 300 and 400K rides

I've got some cateye blinkes on the back:
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