Ratchet bonds are the best debt structure for issuers that you probably never heard of. TVA issued over $1 billion of these in the late 1990s and is still reaping the savings. Read more in Andy Kalotay's Bond Buyer commentary.
Commentary by Andy Kalotay in The Bond Buyeruncovers the hidden value in callable taxable munis. The calls are triggered by tax-exempt rates, while the bonds' worth depends on taxable rates.