For many years now I have called it "soda", but I grew up in the 50's & 60's calling it "tonic". That didn't even make the list.

I read about another bit of interesting linguistic information a while ago. This paper stated that the current British accent did not exist prior to the American Revolution. At that time the British accent was similar to the current Bostonian accent. After the war, British Royalty started speaking with a different accent which was then mimicked by other nobles and it eventually filtered down to the general public. The paper claims there were even school where one could go and learn the new accent.

Now, I have no idea if this is factual or not, I read about it on Yahoo News, but I found it interesting.