I’m going to assume the “magical doubling” is totally legal and tax free. Meaning, the bank won’t come after me for the accidental deposit in a few days and whatever process added to my account also sent money to the IRS in my name to pay the inevitable tax bill. Obviously, my answer would be different if this weren’t the case.

It would make a small improvement in my life, but not much. I’d lock the extra money away in savings and likely wouldn’t touch it, but it would provide peace of mind in case things went south financially.