With this sort of contract, the owner of a big, highly appreciated stock position gets an upfront payment from an investment firm--typically for 75% to 85% of the value of his shares--in exchange for agreeing to deliver a variable number of shares or cash in the future, with the exact amount dependent on how the stock performs.

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The PVF allows the investor to receive an up-front payment (typically, 75-85% market value) in exchange for delivery of a variable amount of shares or cash in the future, at which time the capital gain is realized for tax purposes and the tax on the capital gain is paid.

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The value of a network is as subjective as it is variable.

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During the stockmarket bubble, however, a lot of people borrowed from their banks to buy variable policies, and lost money when the interest payments on their loans started to exceed the value of the policies.

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