To quote an old joke, “I’ll keep farming until it’s all gone.”
I would not buy a mansion, or a jet plane, or a limousine.
But I would rent them for a few days, just to see what it’s like.
Is a billion dollars enough to start a new university? Or would I have to bribe my alma mater to re-name itself after me?
I would do a LOT of traveling. My goal would be to visit every country on earth, every state/province on earth, every county/parish on earth, and the most important cities on earth.
First I’d put it all in a simple savings account at my credit union (they’d all have heart attacks from joy). I mean, why would I want to invest or “manage” any of it? It’s not like I need to grow it any.
Then I’d quit my job.
Then I’d buy a midsize house, cash, somewhere in my current area but possibly more conveniently located to the friends and family I have here. It won’t be a mansion, but it won’t be a fixer-upper either.
Then I’d furnish that house with medium-quality furnishings demonstrating no taste whatsoever.
Then I’d move into that house.
Then I’d hire a cleaning service to come out to the house twice a month and somebody else to manage (or pave) the lawn.
I won’t replace my car immediately, but when I do it will be with a modest car geared for comfort and functionality, not style or speed (of which I have neither). So, probably another Kia Soul. Though if self-driving cars happen I will definitely get one of those. (Especially if it’s a Kia Soul.)
I’d set up a regular bi-weekly transfer of $1500 or so from my savings account into my ‘day-to-day’ account. This covers bills, regular expenses, and a generous frivolity fund. Disasters and major expenses like car replacement can be paid from the big account, but fun stuff comes from the day-to-day account.
And so would I live, quietly entertaining myself until I died and gave whichever of my surviving relatives that Idaho hands my remaining cash to a chance to ruin their lives with the money.
Oh, and prior to that I would refuse to give any money to anybody. That’s just asking for trouble.
I’m retired, and my house is paid off and I already have a financial advisor. After he picks his jaw off the floor, I’d meet with bigger wigs at his office.
I’d pay off my son-in-law’s law school debt, and pay off their house, and buy a house for another daughter. They are both doing quite well, and don’t need a ton of money. I’d put money in a trust for my grandchild and all future grandchildren. I guess I’d buy a new car, though I like the one I drive fine, and my wife has a new car already.
Our house is already too big for us, so why move? Travel a bit more, first class I suppose.
Mostly I’d put a lot of money into the local food bank, into the ACLU and Planned Parenthood, some into my college (though they have tons of money already) and I’d probably donate the maximum allowed to all Democrats running for Congress next year, and a bunch to the presidential candidate.
Oh, and a gift of a charter membership to all active Dopers.
And I’d still have money left over. The problem, alas, is that money doesn’t let me read any faster. Time is what I’m poor in, even when retired.
First I would put most of it into an index fund based on a major exchange. Then I would get into one of those jet timeshares so I could go where I want, when I want and skip all the TSA shit (and the equivalent in all other countries). Then I would go off and do my mathematical research, same as now.
BTW, I know a guy with $100,000,000 who mainly does his research and little else.
I’d be the kind of billionaire the very thought of whom makes good leftists foam at the mouth: self-indulgence on a Cyclopean scale. I’d spend money on exotic pets, pretty young men, luxury travel, top-drawer drugs, and a cigarette holder made out of black amber. I’d be a patron of the kind of weird abstract art that confuses and irritates normal citizens. And I’d make damned sure I had a shit load of media coverage, too.
Because I’m basically good-natured, I’d also pass out c-notes to panhandlers and make reservations for 13 at the snobbiest most elitist restaurants in the USA, and bring raggedy street folks as guests. Otherwise, all my charities would be animal-centered ones
If I had a billion the first thing I would do is consult with the best nursing home in town, and set aside enough money, plus 10%, so that when the time comes I would be well taken care of. I would set up similar funds for my immediate family.
Then I would begin a long trip, while I planned for the rest of my money. I might be gone for at least six months.
I know that at least half of the money would be given away. I would have a law firm on retainer, so that when I heard of a local need, I could call the firm and have them send a check. School needs, some hospital bills for a couple of friends, two animal shelters I hold in high esteem. A good chunk to my church. I would establish a nursing scholarship named for my mother, a teaching scholarship for my maternal grandmother, a scholarship named for my paternal grandfather, and a couple others.
I would rent a nice apartment, and give away my house. I would eat out a lot, but still have fun cooking at home.
Oh, almost forgot, I would finance the Dopefest to end all Dopefests, renting out a block of rooms so folks could afford to come.
Well some posters on here claim they would commission studies, I on the other hand would crush my enemies, see them driven before me, and hear the lamentations of their women.
First off you wouldn’t be insured if you did that. Also, you would get a horrible rate of return.
What would actually happen is you would be elevated to the private client division of the bank you are dealing with. They would offer to help you (e.g. sell you stuff) but you also get a higher level of service.
In practice with a billion dollars though you would likely end up using a private office. This is an investment firm that you own that invests your money for you.
I’m feeling like people aren’t really understanding how much money a billion is.
A billion dollars invested fairly conservatively should grow at 4%, which is 40 million a year.
So I’d give out large grants to various charities and people.
Even 2 million invested wisely can make life much much easier for a family for several generations. The problem is finding a family that’ll use it wisely and not squander it. A lot of people blow everything they have no matter how much it is. But if there was a family that was struggling but I knew could handle money responsibly, giving them 500k to invest so their lives could get a lot easier (eliminate their mortgage debt, car debt, student loans, etc and have money for daycare) that would be nice.
I think I’d start a charity like the macarthur genius grants for fields like neuroscience and AI.
Mostly cocaine and hookers probably.
Billion with a ‘B’?
I’m lucky enough to know a couple of people with incurable, life-ending disease. In the first case, I’d pay off the family debt, establish a trust that covered every possible foreseeable expense, times ten. The other, never a worry about any want at all. Amenities. Send all their kids to college, full ride (except the ones that already have that, smart kids!).
Pay off Steve’s debt, buy him a stupid sea-worthy sail boat. Convince him to go through with the divorce he wants so bad.
Buy a company. Make my kid work at it 40-50 hours a week for 30 years, then its his.
Expand my modest car collection. All new acquisitions would be conspicuously immodest. Maybe sub-contract Leno’s guys to work on them now and then.
A small horse-cart.
The rest? Buy new collars for the crew at PetSmart. That should about kill it.
My standard practice with windfalls is to invest half (including paying off debt like a mortgage) and spend half. 
My parents left me a house, and part of my retirement income comes from investing half of that.
In the meantime I spent some of the rest on:
- trips to Las Vegas (no gambling, but I now have friends there :))
- safari to Africa
- model railway (here in its early stages)
If I had a billion to play with, my spending would include:
- having a small castle built (moat, drawbridge, portcullis, battlements, secret passages etc.)
- turning one of my roleplaying campaigns into a computer game
You posted this while I was typing. I change my answer.
If I had a billion dollars, I would specifically set out to do some investments of the kind which do need multiple million dollars. I don’t know how long would it take me to burn through it, but I’d target my hopefully-productive investments into companies which passed my ethical sniff test (thus helping ethical companies) and I’d establish grant programs to assist researchers, entrepreneurs, teaching and healthcare systems, infrastructure programs… The kind of investment which pays back not in money but in better lives.
And if I had un billón de euros, the above times 1000 
Even with all the flights to see this school or meet that minister, that would take a long time to spend!
I think about this a lot.
I could live okay on $1m. It wouldn’t be a luxurious life, but it could be done. This is assuming basic low risk investment at a bank, and then a quiet retirement in an insignificant corner of the world, perhaps with a supplemental income as a backup and to keep me sane.
With $2m I would do the same but with a nicer home and location. With $5m I could be a bit more luxurious, and share some without much concern. After that, any higher and it gets into crazy levels of luxury. I might put some into running a business or being a silent partner in something I believe in, or helping friends and family by quietly increasing their standard of living too, that kind of thing.
This is assuming it is the amount described, in cash. No tax shenanigans reducing it by half or whatever, the net amount I have is $x million.
I’d give a quarter to charity, then get to work on spending the remaining $999,999,999.75.
A billion really isn’t that much money. I’d move to northern Idaho with my friends and family and start the compound we’ve been talking about. First off I need 2,560 acres so we can live a mike from our boarders. That will run 100 mil. Then I need to set up the society, agriculture, education, businesses to support ~160 people or 40 families
We’ll need to raise 60 klbs of meat each year so that will take up 4,000 acres and we’ll need another 4,000 for farming. 40 houses and business will burn 200 cords per year so we’ll need 800 acres of timber.
In the end I’ll need about 12,000 acres of good land so that’s half my billion and the. To set up the rest of the businesses and infrastructure will easily take the other half. I planned it all out once and I needed like 5 billion to do it right but I could squeak by on a billion.
Yes. The sum is staggering and warps the world. It’s many orders of magnitude more than you can deal with by yourself. So thoughts turn to putting the money to work for good causes.
And yet, there are quite a few multibillionaires. Left long enough, you might start believing that you’re somehow special just because, you know, of the huge sum of money.
Conclusion: I really don’t want a billion dollars.