How to check available credit card balance online?

Is there any way available balance of a credit card can be checked or predicted on the internet without necessarily accessing the issuing banks online banking facility - A mysterous friend of mine just told me it's pretty possible. Can anyone help?|||The only way i can do it is to sign up for internet banking and access the account that way.|||Maybe you should ask your mysterious friend.|||No its not, your mysterious friend is just a gimp|||Well, you can check the credit limit of you credit cards via credit agencies such as Experian.|||The only other way to check your available balance is by phone to the credit cards 800# listed on your card.