Besides playing some games to earn Bitcoins you can also make use of so called faucets. These are sites where you can earn some Bitcoins for free at a regular interval.
With faucet Moonbit.co.in you accumulate satoshi over time and claim as often as you like, with a minimum of five minutes between claims.
The faucet will gradually fill up. Initially it increases quickly, but it will slow down over time until you claim. The longer you leave it the more you will be able to claim.
Making a claim every 5 minutes seems to be the most profitable as you can see in the table below (data used is from January 13th, 2016)
|Claim Time (min)||Payout||satoshi/min|
|60 (1 hour)||499||8.32|
|240 (4 hours)||894||3.72|
|1440 (1 day)||1570||1.09|
|5760 (4 days)||2230||0.38|
|10080 (1 week)||2526||0.25|
|40320 (4 weeks)||3345||0.08|
The above payout rates are taken from the site (the rates are adjusted based on USD/BTC exchange rate and their ad-revenue).
If you sign in to the faucet using a Bitcoin wallet address you will get paid weekly on Saturday/Sunday when your balance is at least 5500 satoshi. If you however use a XAPO wallet (sign in with email address) you will be paid instantly when you make a claim.