I'm now enjoying the image of Idaho prancing around in Union Jack boxer shorts scarfing down a chicken tikka cornish pasty and grroving to some Bollywood beats. Though I reckon he knows my tongue was at least partly in cheek.

I can't for the life of me think of a day that could be "British day" as opposed to an English day or a Welsh day or whatever. The 1707 Act of Union would be the only one that made much sense consitutionally, though it would just be an excuse for a load of whinging IMHO. Otherwise, err, the anniversary of universal sufferage? The first album released by the Beatles? Gordo's birthday?