SIVs are the latest talk of the financial press. Structured Investment Vehicles are a way for banks to hide bad loans off of their balance sheets, a la Enron.
SIV also stands for Simian Immunodeficiency Virus, the predecessor to HIV.
SIV was possibly transmitted to humans by people who screwed monkeys.
SIVs are commonly held by people who were screwed by monkeys like Mozilo.