If you had 18.9 billon dollors what would you do with it?

Tithe.

Buy up 5 years of medical insurance for me and my immediate family.

Buy life and burial insurance for me and my family.

Put a million dollars in CDs or something like that. Something safe that will gain interest (3.5% or more each year).

Put aside a tidy sum for my little cousin so he can go to college after high school, and he won't have to break his neck to get a football scholarship.

Help some of the people I have met over the years. Mostly single parents with no marketable skills, who must do very low paying grunt work to feed their kids, and live in very high crime areas. I would pay for them to go to college for a year each, and also give them a monthly allowance to help with child care and bills, so they would'nt have to work as much, and would have more time to study.

Give a goodly amount to a couple who have a little girl with Treacher Collins Syndrome, so she can get one of those extra fancy skilled surgeons like you see on Oprah show.

Set up a program so that people who had to have a limb or limbs amputated can get free of charge highly useful prosthetics, like some of the runners who had leg amputations now wear. Strange looking sprinters legs.

Buy Shamu on Bruck a car of her own so she would never be able to harass another taxi driver again. That witch!

Buy 20 acres with access to water and electric. Then build my own house, learn how to plumb and electrify it myself. (Fun)

Build my cousin and her young son a house, too. He could help, would be a good experience for him. We could have a family farm!

Get a tractor and plant my own food, sell the rest of the food as organic.

Section off part of the acreage for raising a few goats. Sell the milk. Maybe sell baby goats, too.

Build loft barns. One of them could be for family/friends get togethers, complete with a pool table, air hockey, wet bar, and workout equipment.

Hire a big mean man to follow me around with a bullwhip, to keep me from eating anything that isn't on my diet, and to make me workout as I should.

Take my Mom to a different place every six weeks. Taj Mahal, the Coral Palace, Phoenix, the Grand Canyon, the Statue of Liberty, Mount Rushmore, Alaska, Hawaii, the Mojave, the Rez to gamble, the boats in Bossier city, Las Vegas to see all the Elvii, Wayne Newton concerts, Cher's 19th final farewell tour, Barbra's 20th final farewell tour, and anywhere else she ever wants to go.

edited to add:

Crap! I thought you said million, not billion! In that case, I guess i would also give SEVERAL individual Libertarians a portion of the remainder, to be used strictly to make contributions to the Libertarian Party of the United States. Plus I would give a ton to the Red Cross and the Salvation Army, and the Fistula Hospital, and Carl Farley's Boys Ranch and Girls Town. I would also probably hire a grammar tutor. :-)