Quote - For some reason I have not been getting notification of additions to this thread, and have had to look through the last 6 full pages.  Some great entry's in there, its been a fantastic chalange this month. 

Does anyone remember the song:
Knock three times on the cieling if you want me,
Twice on the pipes if the answer is NO.

Wasn't there another one like three steps to heaven as well. 
The French Tri color
The Prince of wales Feathers the **fleur de lis

Boy it goes on and on.**

"Knock Three Times" was a song by Tony Orlando and Dawn

Don't know about the three steps to heaven, but there was "Gimme Three Steps' by Lynyrd Skynyrd

There was also

"Three Of A Perfect Pair" by King Crimson
"Three Times A Lady" by Lionel Richie

My favorite 3 is the "Three Laws Of Robotics" created by Science Fiction author Isaac Asimov.

and for you photographers out there... If you are in Vietnam, it is bad luck to take a photo with three people in it!