If, whilst watching the Equestrian events at Greenwich Park, you wonder how Greenwich got to be home to the Prime Meridian Line - and thereby determine both world time and world longitude - you could do much worse than Episode 91 of A History of the World in 100 Objects, which features the ship's chronometer from HMS Beagle.
It represents technological advancement that didn't get a mention in the opening ceremonies but was arguably much more important than putting men on the moon (as Steve Jones did argue) or robots on Mars. (As undeniably cool as those things are!)
I've been slowly working my way through the episodes of this great series over the past few months - there are a lot of them! - and was particularly pleased to listen to this one yesterday as Darwin and Deep Time both get a mention. (I'd just been updating the MapTime Organic Evolution TimeLine and Keywords.)
So, if you are in London and looking to kill some time between events, download the podcast (or read the transcript) and then visit the British Museum!