Platinum dollars, abbreviated as P$ or pd, is the currency of the BlazBlue world. Compared to real life currency, there is no known comparison in value, but P$90,000,000,000 is enough to buy a small country according to Jin Kisaragi. The Novus Orbis Librarium is said to pay very handsomely in platinum dollars to vigilantes who capture wanted criminals. 
From BlazBlue: Continuum Shift II onward, P$ can be earned in the games through battles and story mode to buy items and artwork from the Item Shop and Gallery.
- BlazBlue: Calamity Trigger, Teach Me, Miss Litchi! Episode 3 - The Shorty and the Hard Guy