My bike and I are fairly visible at night--white light in front, red light in the back, bright yellow fenders, reflective tabs and a light on my helmet. I use hand signals to alert motorists when I'm turning... but I don't think they can see my hands in the dark. Is there anything different I should do when I'm signalling a turn in an unlit place?
I should imagine you should be looking for some reflective gloves. Or even some glo gloves Check these out as an example ... http://lifehacker.com/395978/glo-gloves-reflective-cycling-gear
Also using a good reflective jacket that has good reflective strips down the arms is useful.
Putting reflective bands on your sleeves can help make your movements visible. They don't need to be attached permanently: a second pair of trouser clips works very well when strapped around your cuffs, or possibly the cuffs of your gloves if you're wearing big winter gloves. Something like Ron Hill snap bands (there are lots of equivalent products with different names) are very visible, take up next to no space when you're off the bike, don't encumber your wrists or get uncomfortable, and take only a few seconds to put on when you set off. You might even find your local road safety organization gives away bands like these at events, so they don't have to cost anything.
Wearing reflective (or at least brightly coloured) gloves is also pretty good. Other than that it's all about being extremely cautious.
Similar to the LED gloves, you can always make a signaling jacket.
I bet I know a few of our friends that would be totally down helping with that ;)
I did a project to add electronic Arduino turn signals, brake lights, speedometer, and odometer to my bike. You can check out my project here: http://jdeboi.com/pimpmybike/
I have a pair of these from Sierra Trading Post: http://www.sierratradingpost.com/north-american-trading-soft-deerskin-gloves-reflective-strip-for-men-and-women~p~4617m/ The reflective strip is wide and works as advertised.
If you're biking in cold weather (I'm a Sconnie, so "cold" to me is "25F or below"), I recommend glove liners and/or wristbands; these gloves are a bit drafty.
This problem is easily solved. Just buy some pants cuff protectors ( the kind that keep you pant leg from getting into the chain ), get the ones that have reflective material sewn on them and you can just use these around your arm at night. Any light from a cars headlights in either diredction should light up the reflecting material. Probably cost less than $5 if you want a pair. Most of them are either velcro or elastic for a custom fit. They can be used in all seasons, with a jacket or bare arms.
I wear cheap white cotton gardening gloves on my hands, while biking - they started white and are now a light grey from oil and exhaust fumes. Only cost $2 at the local hardware store.
The other thing is to look for full arm length high-vis jackets or overvests with reflective piping on the arm. Orange is considered better than grellow for night-time visibility.
And ride like they haven't seen you, because they probably haven't.
There are also some (I think experimental) lights with turn signals for bikes.
For example, I once saw an ad for these Lights: http://www.bicygnals.com/indicators.php
A wide front and rear light, both are wirelessly connected together, with yellow lights at the side. One minus point I see for the front light is that it might take up all space on your cockpit, but it seems a pretty reasonable but a little high effort way to go.
Visijax make a high-visibility cycling jacket that also includes battery-powered indicators. It may be the way to go, at least in winter, if you don't mind looking like a bit of a prat.