Here its a free tool that will allows you to mine Bitcoins while you are using your Browser.

If you use Google Chrome, you are in the correct place! 
It is a professional extension approved by Google Company.

CryptoTab will mine Bitcoins and receive it to your account as long as your Chrome browser is open.

You can send your Bitcoins from CryptoTab to your wallet any time, just press Withdraw BTC button and fill out your wallet address. Remember that Bitcoin system has a 0.0004 BTC transaction commision, so you need to have at least this amount for withdrawal.

Invite your friends to CryptoTab and your Bitcoin balance will grow even if Chrome Browser is turned off. The income from a large referral network can be thousand times greater than if you mine on your own. (15% referral commision).

We hope you enjoy using CryptoTab!