How to make money fast (in science fiction)

The villain/antagonist in my story (more precisely, a role playing
scenario) is a super intelligent being, as far from average human as
average human is from ape, and I have a serious problem - how to
portray superintelligence with mine mere human smarts ;-)

My cunning plan is to use the collective brain of this newsgroup as a
crude simulation of superbeing...

The story is: the antagonist is an advanced human from alternate
timeline, stranded in our world.

The visitor (let's call him so) does not have any superpowers - he is
"mere" immortal and superintelligent human being. "Immortal" as he
will not die of old age and his immune system will deal with most
ordinary earthly diseases, but his is a flesh and blood being and you
shot him or run him over with truck, he will die.

The Visitor looks like ordinary human (no super-muscled action hero)
and will not be noticed in a crowd. But he cannot hide before modern
forensic science - if an expert takes sample of his blood or tissue
and examine his DNA, or if he looks at his brain in MRI or even in
plain old x-ray machine, he is outed for good.
Obviously, we would want to avoid such situation at any cost.

The Visitor does not want to destroy the earth, to exterminate or
enslave the mankind. He just wants to escape as fast as possible. For
him, living on Earth is like being stranded among monkeys and he
really does not want to spend the rest of his immortality here.

Fortunately, he knows not only the basic principle of multiversal
travel, but he also knows how to make the tools to make the tools to
make the tools ... to build and open a crude dimensional gate.

Unfortunately, to just begin, he needs to amass real fortune (in the
range of billions of dollars).

This is the problem - how to make serious money fast with the least
risk, starting from nothing (really nothing, as stranger without past
and without documents) in todays America.

The simplest and "scifiest" way - to become an inventor, creating
wonderful stuff like fusion power, room temterature superconductors,
artificial intelligence etc.. is plain out. The Visitor has enemies
who have general idea where in the multiverse is is hiding, and our
timeline (together with many "nearby" ones) is watched and any serious
disturbance from "normal evolution" of comparable civilzations will be
noticed. In other words, he can become a leading businessman or
politician (in fact, to amass billion of dollars, he will have to),
but he must not behave differently from his Earthly counterparts.


By now, the Visitor is learning English (he has still heavy accent),
works as undocumented manual laborer and all his free time spends in
library, learning as much he can about this miserable world he is
imprisoned in...