1. Have some fun. While I hope you'll use at least 75 percent of your windfall on something responsible, there's no harm in having some fun with the other 25 percent.
2. Half of your "responsible bucket" of money should be allocated to long-term needs, while half should go to meet more pressing short-term issues.
3. For the long term, consider buying a fixed-income annuity, a type of life insurance that will pay you and your spouse a set amount of income every month for the rest of your lives. If you buy it when you're young and defer income payments until you're older, the cheaper your one-time, up-front premium will be.
4. The shorter-term issues might include paying down — or paying off — any high-interest debt you're carrying. Down the road, that will save you money in the form of interest you won't owe and in lower interest rates on future loans.
5. If you own a home, consider refinancing to lower payments on your mortgage, or pay it off completely if you can. If you refinance, opt for the shortest repayment schedule you can stomach. Entering retirement with as little debt as possible will make it much easier to deal with unexpected events that come up later in life. (You might also want to use the money to repair any problems with your home that could jeopardize your house's value.)
6. Once you've eliminated debt, put the money you used to spend on those monthly debts into increased contributions to your 401(k) or individual retirement accounts, or consider purchasing long-term care insurance.
7. Create an emergency fund so that your best-laid plans are not derailed by a leaky roof, a creaky transmission, a sneaky disease or a freaky sale.
8. Consider using the money to start your own business — but do make sure it's a well-conceived and well-researched business idea.
9. Take care of your family. If your spouse depends on your income, do you have appropriate amounts of life insurance in place?
10. Finally, and I can't stress this last one enough: Consider using the money to delay claiming Social Security as long as possible. If you can wait until you're 70, your monthly check will be more than 75 percent bigger than if you had claimed at 62.
While I encourage you to continue playing our retirement sweepstakes games, it's worth noting that your chances of winning are much smaller than your chances of receiving a comparable inheritance. Only about 10 percent of people surveyed by the Federal Reserve Board in 2001 said they had ever received an inheritance greater than $50,000. Still … there's no harm in having a practical plan for using any of your "pennies from heaven."
Jean C. Setzfand is vice president of the financial security team in the Education and Outreach group at AARP. She leads AARP's educational and outreach efforts aimed at helping Americans achieve financial peace of mind in retirement. Follow @JSetz on Twitter.