Do you mean where it is serially controlled and only requires a 3.3 to 5 volt supply? You could do that but then each Nixie module will have its own high voltage converter which is a lot of unnecessary duplication.
All SMT construction with 1210 package ultra miniaturized transformer and MHz range switching frequency plus SOT883 transistors and DFN package MCU, I see no reason why it cannot be made small enough to even fit in the base of a Nixie tube.
The benefit of having individual converter and driver is that brightness is not affected by other tubes since they don't share the same HV power supply.
At 1k quantity, a tiny MCU, a 1.5w HV PSU and a 10 channel HV driver can cost less than $10.
Hi, I'm sorry to bring back such an old thread, but your comment poked my interest - it could be a very interesting project.
But do you have an example for such a small transformer, available from any of the larger distributors? Would you use a readily available switching controller, or use the micro for that as well?
BR Jonas