I have a really handy light that I use for candling. It works well, I can touch it to the eggs without lifting them out of the turner. It's rechargable and fits in my pocket and it's LED so it puts out good light for candling. The lens is the perfect size for sitting against an egg shell without any extra shielding.
This is a link to the page with the details about the light. http://lighterlight.com/