I much prefer Cricket over '01, but my buddies insist on 301 or 501. So for years I've suggested, mostly in fun, that we play 701 but you have to Double In every 100 mark. Yesterday my best dart buddy Roly said okay, let's try it. So the game is called ROLY01. Has a nice flow to it, don't you think? Start off with a Double of course. When you pass each hundred, ie 600, 500, 400, etc, you have to hit another Double to continue. And then to checkout, you have to Double Out of course. We developed the rules around the 100 marks as we went. On the turn you are crossing the 100, all your darts count, and you don't have to attempt a Double that turn - although it's a good idea to, missing inside of course. If you cross the 100 on your first or second dart, and you hit a Double that turn, you simply keep going. If you start a new turn after crossing the 100 without hitting the next Double, nothing counts until you hit the next Double, just like when you began the game. You have to hit 8 Doubles to win the game. It's a lot more exciting than straight 501 and is major Doubles practice.