A weekend or two ago it was open day in London - lots of buildings flung their arms open to the masses. More importantly, you could also wander around the City Square Mile and take pictures of buildings to your heart's content, without being arrested as a terrorist.
I tried my hand at some architecture - the Gherkin (from the outside) and the Lloyds Building (mostly from the inside). Here's a link to flickr for the set, if you fancy seeing them all.
But here's the one I like best: the Gherkin, reflected in a watery silvery way: