Keith Richards, of the Rolling Stones, from a post on the New York Times' great Freakonomics blog this afternoon:
"We left England because we’d be paying 98 cents on the dollar. [This may sound like an exaggeration, but likely isn't.] We left, and they lost out. No taxes at all."
There's more on this in the band's documentary Stones in Exile.
Matthew Sinclair co-authored a report on entrepreneurship with Jonathan Scott last year. They showed that the 50p rate of tax could mean a top combined marginal tax rate of 92 per cent for successful entrepreneurs on income earned, saved, invested in a company and passed on to children.
With tax rates like that, there could be a few more entrepreneurs in exile.