While traditionally one would trade bonds to make such bets, by entering into either side of an interest rate swap agreement, you would gain immediate exposure to interest rate movements with virtually no initial cash outlay.

FORBES: Demystifying The Swap Market

One of his clients who lent her grandchild money for a home down payment created a written agreement that included the loan amount, interest rate and monthly payment.

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While 90 percent of consumers chose the no-interest option, one-quarter of those failed to pay off their balances in time and were hit with the 27 percent interest rate, frequently because they didn't understand the terms, the agreement said, citing Schneiderman's findings.

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Typically, one series of cash flows would be considered the fixed leg of the agreement while the other would be less predictable, such as cash flows based on an interest rate benchmark or a foreign exchange rate, usually referred to as the floating leg.

FORBES: Demystifying The Swap Market