What would you study?

[SteveDallas]

Originally Posted by Undertoad

If you already have an undergrad degree, the doctorate will take you 3 years . . .

Few people complete a doctorate in this amount of time. (Maybe two years for courses... but then it's the dissertation that kills you.)

But I'm quibbling; call it six years. As you say you still have a large pile of cash. Assuming you're still alive when you're done; you're sure to incur the wrath of your non-rich graduate student colleagues as well as your non-rich professors (without whose approval you'll never wear that hood).