Dr. Allen, a retired surgeon in his early 70s, is not well. His big concern is his spouse, who is a spendthrift, knows nothing about finances and has never missed a sale.

Through great effort and secrecy, Dr. Allen has accumulated $3 million in his individual retirement account. He is concerned about what will happen after he dies. Will his wife run out of money? A virtual certainty if she is the direct beneficiary of his IRA and lives to her life expectancy, according to his calculations.