Well is "SOMEBODY" threw an egg at the Queen, the they would be arrested, charged with assault, treason, probably a load of different laws too and ultimately locked up for quite a long time. On the other hand, it would be the win of the century... Tough choices. Nah in all seriousness, i wouldn't try it.
Jack's right, an assault against the queen like that would be a serious crime. Possibly could amount to treason as well. Just discussing or planning of something like that could be classed as treason!! haha well not for me cos I'm not a UK citizen. Throwing an egg at someone.. well that's just bad taste really imo anyway. Not to mention she is a very old lady, what if she had a hard attack and died....! that person'd be up for manslaughter, and I think that's called regicide in this case.. And you generally don't get a worse crime in any country than that.. All this over an egg? certainly not worth it!