Even the Queen got asked this. While walking in Balmoral some tourists asked Her Majesty if she'd ever met...herself. Banter-meister that she is, she pointed at her security guard and said "No, but he has".
5. "Your accent is so cute"
Actually, this is fine. More of this please.
99 times out of 100 this is passive aggressive. You got that? Mate?
7. "Say something British!"
For some reason the reply "the Act of Union" doesn't seem to do it.
8. "Shaaat aaaap you sccchhhhlaaaaag"
Or "You sound like you're from Laaaahndahhn" or any other attempt to do your "really good" British accent. First of all, there are 56 accents in the British Isles, so unless you have lungs like Michael Sheen, cease.
9. Anything to do with money
Unless it's ABBA, no.
10. "Do people ever tell you that you look like Harry Potter"
Admittedly this is better than Will from the Inbetweeners.
11. "G'day mate"
12. Calling British people "Rosbeefs, Britishers, Limeys, Pommys, etc"
Nicknames given us by the Frogs and Yanks and Krauts. UN-BELIEVABLE.