My husband (english) loves this one.
A member of the Barmy Army, sick of sitting through match after match of cricket with England Losing, goes to the doctors and says
"Doctor, I'm sick of being english. I want to become a Kiwi. What do I have to do?"
Doctor: "Easy. Just a simple operation. We put you under and take out half your Brain."
Englishman: "Ok, lets do it."
After operation, doctor visits the englisman in his recovery room.
Doctor: "I'm really sorry, but I have some bad news for you. We didn't remove half your brain, we accidently removed all of it."
Englishman: "No worries mate!"