Build website to crowdsource $292,201,338. Buy all the lotto tickets. Pay back investors 150% of their investment. Make ~ $69.5M.
(assuming lotto tickets are a $1) (someone else can figure out the break even point after taxes)
It's the real free money part!
Crowdsource ~$146 million and only buy half the lotto tickets. For each of the ~11 million combinations of regular numbers, buy 13 tickets covering half the possible powerball numbers.
Assume you win the $800 million jackpot and lose 50% to taxes, you have $400 million left over. You spend ~$292 million to double your investors money and have ~$107 million left over.
Assume you don't win the $800 million jackpot, you still have 13 $1 million tickets left over. You can either pay that back to your investors, or keep it for yourself and point to a clause in a contract they signed saying that you'd only pay out if you won the jackpot.
Somehow I doubt it's legal to do something like that, but it's interesting nonetheless.
Gambling losses are tax deductible as expenses against gambling winnings.
Going with your scenario, if you spend ~$146 million and win ~$800 million, you'll be taxed on the ~$654 million profit. Off the top of my head you're looking at ~$400 million in after tax winnings.
So the investors get their ~$146 million back and then take a share of the remaining ~$400 million.
If you spent $500 million on tickets and won $800 million, your tax liability would only be on the $300 million profit.