LLC's began in Wyoming and have spread to all the US States. An Indian tribe is a tax-exempt sovereign entity. Many have their own corporations code. They are used for casinos and other enterprises. A policy can be used as a wrapper for a hedge fund to insulate the investor from annual gains arising in the fund.
Private foundations are easy to create, but are subject to strict rules of governance.
They are easy to create. They may be used to simplify the grantor's tax reporting obligations. Fully distributing trusts are similarly transparent. A similar regime can apply to a royalty company owned by foreign persons. The VEBA is a Voluntary Employees Benefit Association.