They're all PCs and I really hate it when people argue that something not running Windows isn't a PC.
I haven't really thought about it, but I think I lean towards machine these days while I used to use box a lot back when I first got into IT. I still use it occasionally though, probably mostly when someone else starts the conversation by using it.
I think all sides have been equally guilty of distinguishing between (IBM) PCs and the rest of the personal computer world. Mac fans of past years definitely didn't identify themselves as "PC" owners. And mainframe and Unix/Linux users have done their share of calling the IBM stuff PeeCs or, even worse, WinDoze. And I don't think the nicknames were an indication of fondness. Of course, it doesn't help that the term "PC" was part of IBM's trademarked name for their desktop computers.
Personally, I don't think about it much. And, yeah, I think I use the term "machine" or "box" sometimes, too. Probably "box" most frequently.
They are all personal computers but personally I call windows machines PC's, so do a lot of people, I think in some cases PC!=Personal Computer anymore.
And I tend to correct people who try to differentiate them that way because it's stupid and usually some Apple douche trying to be condescending.
Nah I think it makes sense, PC's don't nesecarily mean Personal Computers anymore most of the people I talk to tend to say PC when they mean Windows Computer, it works, and it's not people being a douche (I just found out what a douche was... wow...)
Except that it does and maybe I'm being emo about it, but whenever a Mac user refers to a Windows machine as a PC there's a condescending tone that goes with that because they don't want their beloved Apple products lumped in with common Windows machines.
And sorry about the US-centric slang, I didn't even think that you might not know what was meant by the term douche/douchebag. =)