From the creators of cryptopyramid, which has been making payments since March 16, 2015:

http://doge.cryptopyramid.com/?ref=71

  Registration.
  Anybody can become a member for free by providing his/her permanent withdrawal address and captcha.
  Each member receives a referral link to attract newcomers.
  Each member receives a permanent address to deposit funds. Minimum amount per deposit is 3 KDoge.
  If newcomer follows the referral link and gets registered within 90 days, then he/she becomes a referral of the link owner (and the link owner becomes a sponsor of newcomer).
  If newcomer didn't register via referral link then he/she becomes a referral of a random member.
  Money distribution.
  Each member pays 100% of their deposits in accordance with the distribution algorithm[2], and receives 50% of their non-deposited income (earned through random and referral payments) to their withdrawal address in accordance with the payout algorithm. [3]
  Member's income = member's deposits + referral payments + random payments
  Member's expenditure = member's withdrawals + withdrawal fees + sponsor payments + random payments
  Member's balance = member's income - member's expenditure
  Withdrawals and all other outgoing payments are done automatically when member's balance hits the threshold of 20 KDoge.
  Each member's chances to receive random payments or to become a random sponsor of newcomer depend on sum of his/her deposits. [1] Thus if member doesn't deposit anything, then he/she is unlikely to receive random payments or random referrals.
  Each member any time may deposit any amount to his permanent deposit address to increase his/her chances of being selected for random payments and to increase the amount of money can be received at a time.
  Rules are a subject to change.

[1] The following algorithm is used to select a random member:

  Assume every user has deposited ([amount they have deposited] + 0.1) KDoge
  Randomly select member, linearly weighted based on account value associated with membership as determined by step 1

[2] The following algorithm is used to distribute a member's deposits and income (money from referrals/sponsors and random amounts received) among members:

  selectedMember = select random member[1]
  send 49% of their income/deposit to selectedMember
  send 49% of their income/deposit to sponsor
  send 2% (the remainder) of their income/deposit to CryptoPyramid as fee

[3] The following algorithm is used to distribute member's non-deposited income (earned through referrals and random payments) when balance hits the threshold of 20 KDoge:

  send (money left / 2) to member's withdrawal address
  distribute the remainder among members[2]