I have hashflare.io. Referral code: 9B5028CE. I warn though if you can not buy enough contracts to earn 0.05 btc in a year then it is not worth investing. At the time when I was making the investment I did not imagine hashflare would end their open ended contracts but now will likely have a lost as my initial investment has only earned my about 0.01 btc in the past 8 months. Unless hashflare lowers withdraw fee to 0.01 I will not be able to withdraw any earned btc. Sucks.