It is also a clock (HHMMSS) but I will also scroll the date across it with the month in words.
I've now built 3 different VFD clocks already, all get their time from NTP, and published one here: IV-18 Vacuum Fluorescent Display NTP Clock
If you want to dim the display, you can do so be running blank cycles, that is a cycle without displaying a digit. Of course, that will mean you'll need an LDR, resistor and free analog pin to sense the ambient light level.