I've found these items indispensable when shooting at night:

Red LED light: to set aperture/shutter speed at night and not loose night vision, http://www.gerbergear.com/Tactical/L...light_22-80016

Green laser pointer: I can point the laser at the subject and focus till the beam is a pinpoint on the ground glass, very helpful in dim light or when using slow lenses. http://www.laserpointerpro.com/2pcs-...en-p-1237.html

Night vision goggles/monocular: when I need to hike a few miles in the woods at night to get a sunrise shot and general nighttime use. http://tnvc.com/shop/anpvs-14-milspe...al-forces-kit/

Gerber multitool: A must have! http://www.gerbergear.com/Industrial...-Tool_22-41470

Chemlites: If I need to mark a hard to find trail out of or into the woodline, just hang them on a tree and they can be seen for a good 300-500 feet. They are also good for keeping in your bag to light it up at night. http://www.emergencyresponderproduct...rchwiroho.html