Fire Lotto
While not a 100% original idea, lotto using crypto, it is an ICO that already has a working product.
The lotto itself has already been launched, the contract is up, and you can review the code on github. https://github.com/firelotto/firelotto
The ico is currently running with 1FLOT=$0.35. Holding tokens gets you commissions on tickets sold.
Chack it out:
https://firelotto.io/account.html?ref=4733