I have to agree about Bob Geldof. I carried him on one of my flights and he just grunted answers, no eye contact at all and no please or thank you. He basically treated the cabin crew worse than a servant, as if we were the lowest of the low because we were serving him. Shame.
I have also carried Gordon Brown and I found him to be a very charming polite man who did not want much but was always smiley and pleasant.