Sierrahash is a mining company.
Users - 263246 (as on 06 Dec 2017)
It is giving away 150GH/s for Free. This gives an earning of 0.00003750 BTC daily.
However withdrawal is not allowed until you have actually bought mining power.
Mining Power - 400 GH/s for 0.001 BTC. (Min investment)
Return in 10 days 0.0013750 (More than your investment)
Min Payout 0.0002 BTC (Min 24 hrs gap for next payout)
It started in middle of Nov.
I am taking payouts daily from here and so far they are instant.
You can join Free, get Free 150 GH/s
In 30 days you will have 0.0011250 BTC
Check if the site is still paying.
If it is, you can invest 0.001 BTC and withdraw 0.0011250 BTC (No txn charges being deducted)
This ensures your seed money back.
After that all earnings are bonus.
One never knows how long this site can keep paying