Rolling in Mystery Money

My checking account has a little over $2M in it. The bank is calling me several times a day to pitch better ways to invest it. I told them to leave it in the checking account. I don't even know what to do with $2M - do I need special paperwork for that much money? What about taxes? What if it isn't mine? Where is it coming from? Aside from food and my husband's laptop, I haven't spent a penny.

Not word from Steve on our mysterious benefactor -- he probably forgot. Guy's a total flake, I can't believe he's the smartest guy on the planet.