Nationwide, states hold more than $13.4 billion in unclaimed property.
Make sure you check with every state in which you have lived (unclaimed property is generally turned over to the state of your last known address as reflected on the records of the business holding your money, stock, etc.).
Do not assume that the business has your last known address, in which case the property is supposed to be sent to the state of incorporation of the business. Many times the state of incorporation is Delaware, New Jersey, New York or California. You may have to check your names in those states.
Keep in mind that if someone calls or writes to you and asks that you pay them money for the successful return of your unclaimed property, you probably have some lost money out there somewhere. The folks who are contacting you are called "heir finders." They are not likely to contact you unless they believe that they have found property belonging to you. Heir finders generally charge a fee to locate and help return unclaimed property to you.
All of the states provide the same service to you with no fees charged.