Investment banking
"...another hedge fund manager explained Icelandic banking to me this way: you have a dog, and I have a cat. We agree that each is worth a billion dollars. You sell me the dog for a billion, and I sell you the cat for a billion. Now we are no longer pet owners but Icelandic banks with a billion dollars in new assets."
Michael Lewis author of:-
Liar's Poker - His experiences as a bonds salesman around the mid eighties
The Big Short - The 2007/8 banking crisis - people who saw it coming.
Boomerang - Not read it YET
Eye opening books from an (ex) insider.