Did you ever notice GTalk chat application window showing the word BP in blue color? If you have not, try now. When you send a chat message with a word BP, GTalk shows it in blue color.
Few minutes I wondered, what made GTalk to display BP in blue color? Then a simple Google query found answer to my question. The answer is very simple, BP is a smiley in GTalk and GTalk displays all smileys in blue color.
Hmm...That is news to me. I never knew that BP is a smiley. Digging little further on the net, I got complete list of smileys supported by GTalk. Here is the list and the below image which shows how these smileys look in GTalk chat window
;-| ;-O ;-x ;-P ;-D ;-( ;-) ;'( ;| ;O ;x ;P ;D ;) ;( ;)
:-| :-O :-x :-P :-D :-( :-) :'( :| :O :x :P :D :) :( :)
B) B( Bx BO B| BD BP