The State of California has a collective $20 million that belongs to taxpayers and wants to give it back. According to the Franchise Tax Board, almost 47,500 tax refunds were returned by the post office because people had filed their returns and then moved without updating their address. The Tax Board’s website — where the number one question is “where’s my refund?” — is the place to make changes of address, whereupon the tax refund is automatically sent.