Did you know that the Bank of England makes a £1,000,000 (£1m) banknote (also called a ‘Giant’)? If you think that amazing, how about a ‘Titan’ (£100,000,000) banknote? They do not issue them to the public (probably just as well), but they do print them:
http://www.bbc.co.uk/news/magazine-21145103
--------- Alex Kemp