As in DC, the level of scrutiny in NYC varies quite a bit -- the Metropolitan Museum checks all bags (even makes you turn on laptop computers, just like the TSA at the airport), but nobody searches anything at Grand Central Terminal (though armed guards are everywhere). I haven't been to places like the Empire State Building or the courthouses in a long time, though I bet the security at those places is now pretty intrusive.

None of my city EDC items have raised any eyebrows or even attracted much attention (but that may be because I'm short, Asian-heritage & female). I have a CMG Sonic flashlight on my keychain and, in a zipped mesh bag: extra Metrocard, heavy-duty cable-ties, SAK, mini-FAK, matches, HD needle & thread, HD plastic trash bags and safety pins. (After reading some of the other posts, I think I'll add a whistle and some para cord, too.) I usually also have a couple of protein bars and some water in my briefcase.