Is there any way to backup my online wallet?
1) Click on the drop down menu labeled with your account name near the top right corner and click the item labeled "Advanced".
2) Click on the "Wallet" tab.
3) Type in your wallet password in the text box next to the "Brain-Key" label.
4) If you type in the password properly, it should display your brain key in the text box.
5) Copy that brain key somewhere safe. If anyone gets access to those string of words, they will get access to all of your accounts and funds in that web wallet.
6) You can later use that brain key to recover your wallet on another computer/OS/browser (or on the same browser if you were to clear your browser local storage).