Peter from Axiris.be clued me in to a software nixie clock that he made. It is a Windows / Linux piece of software that emulates a six digit nixie clock. If you don't want to bring your real nixie clock to work, this might just be what you need :)
Axiris also sells a few actual nixie clocks as well - both the Manuela and Marcel designs. Go check it out: (Their website is in Dutch but Google Translate works great.)