On another note, what are people doing for power supplies for VFD's such as IV-17/18's? seems to be a lot of conflicting views floating around aout AC vs DC, current and voltage levels. Is there some simple solution to driving these?
There are a couple of different issues when powering VFDs. Ideally, you have two voltages, the anode/grid voltage (24-70 VDC at a few mA), and the filament voltage (1-6 VDC at several to a few dozen mA, floating on a few volts DC). For the anode/grid voltage, there are two common ways to do it. One is to have a positive supply, and switch the anodes and grids between it and ground (like a nixie). Another is to have a negative supply, bias the filament with it, and switch the anodes and grids between it and ground (this is common in industry).
However, AC filament drive is tricky to come by, so many folks just go with a DC filament supply, which is easier, and generally works okay for single-digit tubes. The need for filament bias is greater in these cases, but it's possible to do without it when you're going for a real minimum-parts solution.
There are some canned VFD power supply modules available cheaply on the surplus market that provide a center-tapped AC output, along with a DC supply or two, positive or negative. These are pretty versatile, and can be used with series resistors to adapt to filaments with lower voltage requirements.