How have I never heard of this site before? Here, you can search for your name (or the names of anyone you know) and see if they have any unclaimed money the state owes them. It's through the treasury department and each state has their own site. You can find them here:
http://www.unclaimed.org/ I've found money for a few people so far (my aunt and uncle, Nick's dad, Zoe's parents), so goodluck to you!