30 St Mary Axe, nicknamed "The Gherkin" is also known as the egg shaped building in London. Since it is more bullet shaped, or some might say phallic, there are several other creative names for this building. Whatever you call it, it adds an interesting touch to London's skyline.
I liked the contrast in this photo of the modern Gherkin behind the much older Tower of London. You can also see the Tower of London in the first photo, in the lower right corner.