as the title suggest, a lottery system would be quite neat. it can be daily, or weekly or whatever. prizes can be crowns, gear, ce, mats, recipes...etc
it could also be set up with multiple prices for when you purchase a ticket. like 500 cr for 1 chance (or 1 set of numbers depending on how it's set up), 1000=3 chances, 2000=9 chances, 4000=20...and so on.
Its already so easy to burn hardly earned crowns.