I often run at night. In a urban setting or area where exterior electric illumination is going to screw w/ your night vision anyway, then use a normal headlamp or flashlight.

For 'off grid' like trail running, hiking and such, were you need illumination for personal use only and there is little or no external lighting I use a green flashlight. The easiest way is to use a version of the military's angled GI light or a step up to the Sidewinder angled LED. There are also others you can look for.

Green will not disrupt your night vision and give you a really good, though, not very far lighting. Even will running on good trail. Bushwhacking, your on your own. I have also started to use my new Tikka headlamp that has a larger red LED than the e+lite as a secondary light. Red also doesn't screw with your vision.