I just got back from a 3 mile run - so out of shape - it took me 29 minutes.
I like running at night because there are fewer people to point and stare and because it is so much COOLER. Winter running is fantastic, but I prefer spring and fall because of the cooler air and pleasant smells.
My constant companion used to be a Gamma Headlamp from Alpkit - a nice little piece of kit but I have had two of them break on me - which the company offered to replace gratis but I am still sad about the product. Now I use a Magicshine light from here: http://www.geomangear.com/index.php?main_page=product_info&cPath=4_41&products_id=314
This thing is the brightest headlamp I have ever used and is a Chinese knockoff of a Lupine lamp that is almost 100% close to the original. The Lupine lamp costs nearly 400 dollars if I remember right. I bought the optional headlamp strap( it was meant to be mounted on bike handles I think) and while it is nowhere near as streamlined as a Tikka it isn't all that bad to run with. The battery pack takes some time to get used to - I strap mine on a chalkbag strap and put that around my waist as tight as I can stand which stops it from moving around.
The magicshine is nearly as bright as a cars headlights and will really make sure motorists don't miss you on the side of the road. I have gotten some weird looks from police officers driving by but so far no arrests for lurking.
On a side note, the website where I bought it issued a recall on the battery packs about 8 months ago, I sent mine in and while it took a really long time I got a nice new(better constructed) battery pack that will not burst into flames.