I'd have to say pens too.  I am very particular about my pens, I absolutely refuse to use ballpoints unless I am making carbon copies.  But of course, even when I use ballpoints, they have to be the ones I can tolerate.  I bought my favorite pens when I first started here, and my boss took one look and said "I'm not going to be buying you 'special' pens or anything like that."  I told him I didn't expect him too.  But he is the same way about his pens.  He never uses the company logo pens.  Its always got to be the liquid roller ball or the gel pen with the reflective blue top or whatever.  He will honestly spend 30 minutes to an hour looking for a particular pen before he will sign a document with another one.  

So, I don't touch his pens, he doesn't touch mine.  There's only three people in this office, so I guess I kind of have it good...

Rr