When the government of Zimbabwe finally collapses into oblivion, the entire set from one million and up will available on Home Shopping Network in an attractive oak presentation case for three easy payments of $19.95.
To get a cool souvenir, just search ebay for “Zimbabwe billion.”
http://search.ebay.com/search/search.dll?query=zimbabwe+billion
No $100b yet, but plenty of $50b and below.