I'll second the Science and V&A museums - I was whisked pretty quickly round both of them (Rory was more interested in the shiny stuff than the displays of agricultural and chronological equipment in the first, and we'd been on hour feet for eight hours by the time we got to the V&A) but I'd love to go back and do them properly. The National Portrait gallery was pretty neat, too - like, *so many* originals of paintings you will be familiar with.

Man, I need to go back to London.