The Ten Yard stare (fixed)

winston The oddest phenomenon about the recent boom in fixed wheel riding.....
When I'm pootling around London on my trusted Veto, I often come across this, usually from a rider coming in the opposite direction...a fellow fixed rider staring at you in a "who are you, what are you riding" way and hardly ever with a friendly nod.....you know when two toddlers come across each other for the first time and then just stop dead and stare at each other for about a minute???.....that's what it looks like, has anyone else experienced this?

This type of question seems to pop up all the time on bike forums. Not just fixed riders, anyone.
In Melbourne where there's bugger-all cyclists out my way I'd nod and say g'day to everyone coz you know they're keen.
In London where there's 200 other bikes I'm just not going to say hi to them all. If I notice something odd (most of you fixers are odd looking and smell funny) then I might say something. Usually though, I'm too busy swearing at defenceless old ladies and small children to bother about 'greetings'. ;)