All this crazy talk reminded me of something. No one has decided to use their 300 million to initiate an apocalypse 
.
I think its the idea that if you did happen to come across 300million dollars you would want to live in plush comfort. An apocalypse is kinda the opposite of that. However if you just want to wipe out all humans I spose you could take the idea of creating a Neko-mimi and then by making it a disease, spread it around the world, and effectively turn all humans into Neko-mimis. However whether this is an apocalypse, genecide or paradise will be different for everyone
Luxary > Desire to make Fallout 3 reality
If I had 300million dollars I would prolly move to somewhere. Preferably Japan but I am sure there are other countries just as awesome.
From there I would build a large traditional Japanese castle and build many other smaller houses around it and create my own society from which I would fly over all my friends to live. There would prolly be lots of houses and space left so I would then invite people from BakaBT and other people with the same interests to come join me and make our own little town. Of course I would try to invest around 100mil to get an income back so that everyone in my little town may have a Maria¹ or a Hayate² to serve them.
1: Marias may be exchanged for one that suits your desires better. A range of Tsunderes, Meganekkos and others are available on request.
2: Hayates may not be changed as few others know how to teleport when someone screams their name. Suggestions may be noted and permitted once judged by a panel.
