As Wayne mentioned, the D80's FV lock, in conjunction with a sb600/800 flash, is really cool, allowing freedom to move around while shooting quickly w/o preflash.

One other aspect of the FV function is that you can use it to trigger an optical strobe. e.g., in addition to the SB's, I sometimes use a Metz or 283 (or both) for extra fill light. All are triggered by FV lock function: The SB's are metered, fired and controlled. The optical strobes are also metered, but canNOT be controlled. These 'manual' strobes trigger on the initial flash -and some even stop firing when the "main" strobe (i.e.,SB- or built-in flash)stops- but the camera has no way to control their output. Thus, using this method you wind-up taking lots of test shots to get the power and look you want. Also, in this scenario, I try to block the extra strobes flash behind a curtain, or, in another room, etc., because it's easy to have too much light.

One thing I have found, when using the D80's built-in as commander (in a system with more than one sb600/800), is I usually have to increase the bulit-in's power output to get the dispersion. A system that works well for me is a sb600, on the camera as master, with two sb800 as remotes. I like this set-up because the 600 has a smaller footprint and quicker handling than the 800's, yet, has the power to throw the light around.
smh