The idea for this thread just struck me this morning!
One of my colleagues at work and I (we're at diff locations but great mates) chat quite a bit online. He's an American living in NC. I'm not American. Anyway over the last few months, he's so used to chatting with me that even to others, subconsciously he's started using words like "mum", "fortnight" and started spelling "colour".
So I was wondering if any you TALF-Americans have changed or introduced new words and don't even realise when talking. And then go "hey, THAT's not American! that's so not me!".