I imagine that there will be a lottery that costs nothing to participants and makes the winner the (first) real bitcoin millionaire, the richest man of the world. Not one of the richest, but the richest one with no doubt.
The idea of this lotto is basically the same as
https://freebitco.in/ : every entry will give some free satoshis and participants can play a Multyply-BTC lottery with these satoshis.
Only the maximum prize of the lottery will be 1 million bitcoins (contrary to only 20 bitcoins as in
https://freebitco.in/ today). The probability of winning this huge prize will be about 1: 100 000 000 000 000 per entry.
Nowadays the biggest fiat lottery prizes are about one billion dollars. This bitcoin lottery will give out 50 billion dollars in nowadays BTC/USD exchange rate. But if the bitcoin will become the world first currency then the prize in fiat can exceed even one trillion dollars or TEN THOUSAND TONS OF PAPER FIAT (one 100usd bill weights 1 gram) - the winning amount that is worth its name !
The source of the prize money can be donation or advertisement incomes. As there are no bitcoin millionaires now then the number of donation-makers has to be more than 1.
I bet this project is worth the life work (in Estonian: see ettevõtmine on väärt elutööd).