Gavin Stapleton (dpreview, Panasonic forum, 23 February and 11 March 2004)...
I stumbled across the Sima SL-9, which is a universal 3w camcorder light. It sits on the hotshoe and has it's own 2/AAA battery power supply, it is full manual so need to worry about compatibility.
This has a little more prosfessional appearence to a keylight and won't harm the body of the camera with adhesive. It's only $30us so the price is reasonable and it will offer a better range and perhaps even negate the need for the flash all together in some cases. It comes with the batteries and charger but cannot be operated from a DPS9000 for instance.
I am chasing down availability within Oz before deciding on it, but I figure one of these little beauties sitting on a flash bracket with the flash on the hotshoe will complement each other quite well...
The SL-9 is totally safe, it has just a plastic shoe mount like a slave unit does. It operates on 3xAAA NiMH batteries (600MaH provided) and is charged straight into the unit from 3v DC at 300MaH.
It is good for indoor use only since the light spread is a little too wide. it is much the same brightness as an onboard focus lamp but over a bigger area. I find the light helps me see better than the camera does with it. It doesn't have a dramatic effect on the little EVF in some cases but does aid focusing! I found that the SL-9 makes the camera focus much faster if not better aswell. On 2 occasions it actually made things worse...?
All in all I am only partially satisfied with the SL-9, but considering it's cost and how comparable it is to a standard focus assist lamp I cannot bag it being only 3w output. There is a giant! 20w model called the Sima SL-7 that uses a Sony battery , it seems to have been discontinued but is still listed on some of the less desirable online stores...