What sightings do you have of famous people doing mundane stuff? Prompted by walking past the Sainsbury's Local where I witnessed Peter Stringfellow buying a pint of milk (semi-skimmed).
In another Sainsbury's, I saw David Trimble considering a Secretary DVD. (That Sainsbury's has since been demolished.)
Opposite the Sainsbury's that is now demolished, I once saw Polly Toynbee walking down the street, literally writing in a notebook as she walked like a caricature of a journalist. And just after that I saw a pigeon with a slice of cucumber stuck to its back. The pigeon wasn't famous but it was still a cool thing to see.