Pokerstars and Fulltilt allow you to deposit directly from you bank account. This is call E-check. When you go to withdrawl it will go directly back into your bank account.
The depositing will occur instantaneously. This is done by the site "spotting" you the money and if your check does not clear your account will be frozen. Withdrawling on the other hand may take 4-5 business days for it to arrive in your bank account.

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Kickboyswoop