For battery life estimates, the Arc white CCFL draws about 300mA at 6 volts (1.8w).
For those who want to make their own CCFL light, inverters are generally available in 12 volts and 5 volts. The 5 volts are harder to find, but Electronics Goldmine Has some, All Electronics sells them too, but at a much higher price. BG micro has some 12" blacklight and some colored CCFL tubes. So does All Electronics. They both have 12 volt CCFL inverters
Lowest draw I've seen for 12 volt CCFL inverters is 160 mA, driving a tube about 10 inches long, thats 1.92 watts. More typical is 200 mA, but many drive 2 tubes and draw perhaps 700mA.
As a light source, I'd say they are right in there with luxeon stars for amount of light and efficiency, but I havn't gotten arround to using my light meter to test this and havn't deceided how to adjust for the different radiating patterns.
You can scavenge CCFL inverters from very old laptops, particularly those with cracked screens or otherwise beat up. There is a wide range of types, some are even regulated to some extent. The simplest will have 2 color coded power leads and 2 silicon-rubber leads for the CCFL tube. But more often the inverters have more than just 2 power leads. The extra pins often include an enable that should be tied to one or the other power lead thru a resistor to get the light to turn on. (might not need the resistor, but it is safer). There also might be a brightness control line that is a logic level that can provide various brightnesses thru pulse width modulation, or just 2 levels by tieing it thru a resistor like the enable. You might also encounter an analog brightness control with three pins that would connect to a slide pot. This may give you three levels without the pot; tie the slider to the low end, let it float, or tie it to the high end. Adjustments are generally from mid-bright to full-bright; the lowest light level is still pretty bright.
Figuring out which pin is which can be tricky because of these variations. You can usually locate - by the pin that goes to the broadest trace, which is likely ground. + often goes thru a miniture fuse (check the fuse if you're getting nowhere as one brief reverse voltage will blow it. If there is no fuse, one broef reverse voltage will smoke the trasistors) before going to an input capacitor. If there is an electrolytic capacitor anywhere on the board, it can be another clue as to what is plus or minus. As I said, there is often an enable that must be tied to + or - before you get any light. After that the remaining pins, if any, would be brightness controls of some form. The leads that go to the CCFL tubes generally are on a separate connector from power & control. One pin of the CCFL always goes to a 3 or 4 kv capacitor and then to the transformer. The other CCFL lead may go to ground, or, in regulated CCFL boards, it may go thru a network that lets the board detect current. There are a few CCFL inverters I havn't figured out; I get them to light but they run very hot. I suspect they want a voltage other than 5v or 12v. There are also laptops where the inverter is integrated in with other circuits, like the bias supply for the LCD.
There are some nasty voltages involved with CCFL, perhaps 600 volts of high frequency AC and more when not under load. Shocks from the CCFL leads hurt, but not too bad, and are always accompanied by the smell of burning flesh. Such shocks can sometimes come off the transformer just by getting too close. Unlike the similar inverters that drive strobes, CCFL inverters do not have a diode and capacitor to store up a whopping big charge, so they will more likely hurt and give you burns and are less likely to kill you.
