The British Museum has a show on at present, called Bonaparte & The British. It's mostly satirical prints, but there are all sorts of other assorted bits and bobs, including various Napoleonic 'relics' from, amongst others, the collections of Lord Byron and Lady Holland.
There are, in addition to loads of fabulous (but very anti-Napoleonic) Gillray satirical prints, lots of other artists, like Rowlandson and Cruikshank, and even pro-Boney items, like a bust by Canova, and French prints mocking the British.
Of interest to wargamers there are some beautiful large scale campaign scenes. My favourites are Francois Aubertin's 'Passage du Grand St. Bernard', and Matthew DuBourg's 'Field of Waterloo'. There is also a series of watercolour panoramas of the battlefields of Waterloo and Quatre Bras, painted only days after the battle.
I've reviewed the catalogue that accompanies the exhibition at some length, on my blog, here:
link
… and in a shorter form on Amazon UK's website, here:
link
I hope these may be of some interest?
Cheers
Seb