For some reason, in the UK at least, desks do seem to be measured in mm, yes. It's not a particularly common unit for measuring other large items though, more generally we'll use metres and centimetres (with the correct spelling ;-)
Source: I asked someone who has a Masters in English and forgot most of what she said, so don't hold my feet to the fire on details.
My point is that non-American English spelling is wrong in many cases, intentionally. So don't go around saying you're correct. You mutilated your own language to appease the French.
If we're going to talk about the deliberate sabotage of orthography, then surely Noah Webster's "thru", "catalog", etc are the most outrageous?
That said, as with metre/meter, we have at least salvaged some Websterisms as adding nuance to the language. In the UK, i write computer programs, but pretend to enjoy opera programmes.