You can play Betsoft classics at
PlayAmo with jackpots, like Good Girl Bad Girl for example, where you can a progressive jackpot of up to 1.700.000 credits (of course, provided you bet max).
But we've yet to have seen a major progressive jackpot the likes of the Mega Moolahs in bitcoin, though with the rate of growth of these casinos and popularity it would probably not take too long.