I've always copy and pasted file and folders names into documents (well I'm a lazy typist and poor speller, especially with some designers' bizzare naming conventions). In OS9, I used to single click and wait for it to highlight (as if I was trying to rename the file). It still works in X but here's the killer bit. You don't have to wait until the name is in its change state (which BTW takes forever in X or another single click). But in X, just highlight (even in column mode), copy and paste ahoy. This could be old news but it helps lazy people like me bigtime.
[Editor's note: This is probably a side-effect of the new Finder copy and paste files trick, with this side-benefit of making it easier to copy and paste one or more filenames into a document.]
Mac OS X Hints
http://hints.macworld.com/article.php?story=20011102120811387