I live in Oakmont, Southwest Pennsylvania. It just so happens that Pennsylvania has this little talked about law called the Abandoned and Unclaimed Property Act (72 P.S. Section 1201.1 et seq for you lawyers out there).
According to the Act (from a recent letter from the PA State Treasury), unclaimed property is any financial asset that has become dormant, meaning no contact has been made with the owner after a given time period. After this time, holders must file an unclaimed property report with the Pennsylvania Treasury Department. Similar to your tax return, unclaimed property reports are filed for the previous calendar year and are due no later than April 15. Any holder that does not file a report by April 15, 2008, may be subject to penalties and interest.
Some examples of unclaimed property include bank accounts, un cashed payroll checks, accounts payable or receivable checks, credit balances, gift certificates, stocks and bonds, escrow accounts, money orders, travelers checks, utility refunds, safe deposit box contents and insurance proceeds. If your business has any of these items remaining on the books unresolved, upon tolling the applicable dormancy period, such items must be reported as unclaimed property. The dormancy period of most property types is five years (exception is payroll and commissions which is two years). Please note that writing off these items as income does not constitute an account being resolved.
Short translation is that if you are holding monies (Gift Certificates, Gift Cards, Rain Checks, Credit Books, Ledger Credit Balance, Pre-Paid Accounts or Tournament Accounts) in Pro Shopkeeper, by law you cannot simply expire those accounts at the end of the year and pocket the cash. You are required to turn over those funds to the State of PA. In fact the PA Treasury is holding over $1 BILLION in unclaimed funds! See http://www.patreasury.org/aboutUP.htm for details -- you can even type in your name to see if any of that money belongs to you.
While this only applies to Pennsylvania, many states have similar laws on the books. If you Google "Abandoned and Unclaimed Property" you will see a long list of links from just about every state. So before you set up options to expire Gift Certificates, Credit Books, Pre-Paid accounts, etc., check your state laws (or see your local Certified Public Accountant). You may be liable with penalties and interest for those monies you thought were bonus income!
Enjoy :)