Ok, me again. For low light focusing, I've modified my Stroboframe Reggie (QR-66) with other strobo parts to have 3 hot shoes + metz mount. On one of the shoes sits a 10W rechargable video light. Great for focusing in low light.
Also, when I shoot my Hasselblad without a bracket, I have a modified white LED flashlight with a thin Roscolux filter chunk and old cold shoe off of a *flash*. I also added a touch pad type switch from Digikey and a thin piece of flexible pc board. With this sitting on my prism (or on the side shoe if I'm shooting WL) and the switch double-sided taped to my winder, I can touch the pad to light up my "color-corrected" focusing light. Once I get the focus corrrect, I slide my finger off the pad and onto the shutter release. (Made it for $20.00)
I tried the laser pointer idea about 2 years ago and I realized how rude it was to point a laser diode at somebody's face when you want to focus for the eyes! (not to mention how pissed off somebody gets from the 1mw laser in their eyes!