I can at least insult people in Spanish and Catalan.
Also I believe to know that the German "Tschüs!" ("Bye!") sounds very similar to some Chinese insult along the lines of "Go die!" or "Go to hell".
Monade, thank you for letting us know about your signature! I like it a lot - your personal views, highly encoded. Very Therionish, in a way.
Cheers!
Markus