I had an idea for a money sink, a global lottery.
It would draw every two weeks, tickets would be purchased from the f4 menu.
Tickets cost 500k, for a max of 10 tickets or 5m.
The winner gets 1/2 of all tickets purchased, the other money goes into oblivion.


A possible option is that there are two lotterys, one for lvls 1-99, and one for players 1-30. The 1-30 lottery tickets would cost 50k, but players above lvl 30 can't enter.