I have owned a Coleman Flashcell screwdriver since about 2009. it does not replace the drill driver (Craftsman 19.2V C3 drill driver with lithium ion cells and clutch) but it replaces small powered screwdrivers for doing repetitive screw driving. The no longer sell them and haven't for several years. I've been wanting one to have handy in the garage shop or house rather than running back and forth.

The advantage of a cordless, batteryless driver is that it uses a supercapacitor to drive the motor. The big advantage is that the supercap can be charged in 60 seconds from dead or 30 seconds from half full. That alleviates the problem with cordless screwdrivers i've had int he past that were never charged when I wanted to use them and would take an hour or many more to charge fully, but now its just 60 seconds. The downside is, being a capacitor it has a declining voltage as it discharges. Turns out that its not that bad a deal, it starts out around 200 RPM and when it gets to about half that, its at half charge and you recharge it for another 30 seconds for full charge and 200 RPM again. The slow down is not so bad in my experience.

So I see there's now a new company making supercap screwdriver, called BluCave, and the technology is still TM Flashcell.
I'd recommend this tool after buying one from Amazon and it came in two days with Prime free delivery.
http://www.amazon.com/BLUCAVE-DSD-46...ss+screwdriver
They're selling it for $22.94 which I think is an absolute bargain. Its also for sale at other places (Sam's, eBay) but costs a lot more.

Review:
it has a charger base. The base seems a little large to me and has no keyhole slots for wall mounting, I guess that means you mostly have to have it taking table top space to my disappointment. The base has a line of red yellow and green LEDs showing the charge state and it increments quickly to green when charging in 60 seconds or less. It also has and stores five hex bits and an 2" extension.
It comes with a nylon carry case as well.

The handle is reasonably small, it can be pivoted to be pretty much a straight handle with the trigger switch on the back or a pistol grip with the trigger on the front of the grip. It has a lock so that it won't rotate around while you use it. I found it comfortable to use, particularly the pistol grip. Using the pistol grip tends to control the torque better since the straight more just tends to pull it out of your hand when it hits bottom. But sometimes you want it to rotate rather than jumping out of the screw head or rounding it off. Too bad, no clutch.

It also comes with a LED flashlight head. The head slips on the charging end of the screwdriver over the contacts used for charging. So the five-LED array points away from the driver end. But there's a single white LED on the front that can be used to illuminate the work when driving screws using the pistol grip position. The LED will be below your hand and pointing at an angle to the driver tip. That works well actually. There's a pushbutton switch on the flashlight head to that cycles between the multi LED head, the work illuminating LED and off. There's only one issue - no place to store the head when not in use or charging. Still, you get a nearly free flashlight. It lasts for more than 45 minutes without apparent loss of brightness when the driver is not used and of course recharges in 60 seconds or less.

Driver performance - I drove some 2-inch screws into and out of the same hole in a 2x4 until I got tired and it was still was doing a good job. It's not a heavy duty unit with huge amounts of torque but its reasonable for when you need to take apart or put together something with a lot of screws. Like I mentioned the best thing is never having to wait more than 60 seconds to use it and being able to restore a full charge in another 60 seconds. Being a non-chemical battery it will not deteriorate and lose capacity with usage... they claim 100,000 charge cycles but as an EE, I don't think they even know. I suspect the charge base contacts and switch won't last that long, that's more than for many actuators and connectors. And if you want, you can leave it plugged in the charger forever - that saves you the 60 seconds, and with a capacitor, there's no chance of overcharging and ruining the battery as there was with NiCads and even NiMH. It holds a charge for a pretty long time even when not plugged into the charger base (days, at least) although I did not measure it.

It has a fair amount of power in the capacitor for a 60 second charge. Its good for small jobs that are a bit more than you want to tackle with a manual screwdriver. I gave up testing the light after 45 minutes. I gave up driving 2" wood screws in and out after about 30. Nicely, it holds nearly a full charge even after a week or more without having to recharge it, short as the recharge is..

Overall, I like the unit, for $23 or so its an apparent bargain. It fits the way I work, allowing me to grab it on a moment's notice even if I haven't used it for weeks.