or for more interesting, you can only bet 5times what you have bet previously.

for example

you  bet 0.001btc at the first time , and the next bet with  maximun  0.005 btc.

and if you bet 0.003btc next time, and the third time your maximun bet is 0.003*5=0.015btc.

and so on.

this is far more funny and fairer than the method I metioned in the last reply.

and everyone's start bet is 0.001btc-0.005btc.

what do you guys think about it ,thank you.