Read the post "Cloud Mining Without Investment - The List of Cloud Mining Services That Offer Free Bonus for Just Signing Up (with scams alert)"
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xxx. EOBOT v2 (waiting)

Sign up bonus: 10 GH/s

xxx. HelixxMine (waiting)

Sign up bonus: 21$ (for 1 year BTC mining)

115. CryptoFly (waiting)

Sign up bonus: 1.83 GH/s (for 7 days)
Note: Withdrawal is available only after the first paid contract.

129. BitHash

Sign up bonus: 0.001 GH/s

131. hexxo
Sign up bonus: 300 KH/s
Note: Your account will be suspended as inactive if you don't make a deposit.

138. CoinMining
Sign up bonus: 1250 GH/s
Note: To receive payout from FREE TRIAL CONTRACT you have to purchase a mining contract.

142. Micro-BTC (warning: login problem!)

Sign up bonus: 15 KH/s
Note: You must purchase hashpower for withdrawal unlocked.

144. BTCSweet (waiting)

Sign up bonus: 5 GH/s

145. ETHSweet (waiting)

146. BTCProMiner (warning PIN problem!)
Sign up bonus: 40 Satoshi per minute

149. 247 Bitcoins

Sign up bonus: 0.00000660 BTC Daily
Note: You must have deposit to withdraw.

151. BitFireMining
Sign up bonus: 100 GH/s
Note: bonus hashrate has expiration.

152. KryptoTrend (withdraw pending since 2018/01/09)

Sign up bonus: 0.00500000 BTC

153. CryptoClub (warning: login problem!)
Sign up bonus: 10 USD

168. Rub-Mning

Sign up bonus: 1 KH/s (1000 KR)
Need a Payeer address to withdraw. Payments to Payeer are available to users who have replenished the balance by at least 2 rubles or earned 100 personally credited referrals.

169. Faucet Cloud (waiting)
Faucet.Cloud - Cloud Mining
Sign up bonus: 10 USD

178. WormMiner (waiting)

Sign up bonus: 1 Mining Machine

192. Bitmining24 (waiting)

Sign up bonus: 20 GH/s

193. ArgusMiner (waiting)

Sign up bonus: 20 GH/s (1 Year)

200. MineBe (waiting)
Sign up bonus: 500 RUB

206. fernandos2

Sign up bonus: 0.0015 rubles/60 minutes
Note: Need a Payeer address to register.

208. CoinMix (waiting)

Sign up bonus: 1 GH/s

230. AutoMining

Sign up bonus: X1 power

235. Hashter
Sign up bonus: 100 GH/s

238. Dellmaria

Sign up bonus: 10 GH/s

239. DogeMiner
DogeMiner - Mine and Earn free Dogecoin
Sign up bonus: 1 DH/s + Faucet

240. IWex

Sign up bonus: 200 GH/s

241. Hashtopia

Sign up bonus: 150 GH/s