i have two things to talk about
firstly, when the pope came to england in 2010 a modern classical composer (James MacMillan) was asked to write a fanfare for the occasion. you might expect the fanfare to be bright and cheerful. but no, MacMillan is a modern composer and he really likes dissonance... so the fanfare sounds like it's announcing the introduction of an evil character in star wars.
(the fanfare starts at 0.15)
secondly, i heard an advert for this on the radio a few weeks ago, and it should be super-mega-awesome-cool
probably the best orchestra in london, performing in tragalgar square for free ! the evening of saturday 12th may.
performing works by Stravinsky: Fireworks, The Firebird (suite) and The Rite of Spring. The Rite of Spring especially is awesome. it gets really violent in places. and if it's your kind of thing then have a look at the score and have your brain melted by the time signatures. and everything else.
in fact, i'd say that The Rite of Spring was probably the best pieces you could play someone who doesn't know much classical music and assumes it all sounds like mozart.