Credit card fees

No it casn not be done in QB

and if you are in the US, it may be illegel to do so

Surcharging for using a CC card is illegal in the following states: California, Colorado, Connecticut, Florida, Kansas, Maine, Massachusetts, New York, Oklahoma and Texas.

You can however offer a discount for cash in those states - except in New York where no cash discounts are allowed

New fed laws went into effect in Jan, 2013 allowing surcharges providing the retailer
make customers aware up front that there is a surcharge and how much for using a CC - at the store entrance and at the cash register or if an online store at the first reference to accepting CC for sales

You can not use a surcharge for debit cards or prepaid cards (so personally I do not see how you could do this surcharge thing with online payments anyway)
surcharge fees must be itemized on the receipt, in store or online

an overview
http://www.cardfellow.com/charging-customers-a-credit-card-convenience-fee-at-check-out/

 Rustler covered most of the key points and the info he linked should be helpful. I would recommend speaking with an attorney about what your specific options are, especially if you have customers in multiple states. Also, be certain that this "cash discount" does not become a profit center. IE, if your average monthly effective rate for credit card fees is 2.1% and you attach a 5% cash discount, that could become an issue. Finally, with the way the industry has adpoted "cash discounting", I wouldn't be surprised to see a pushback from the card companies and regulators at some point in the future. Visa, MC, etc. don't want consumers knowing that merchants pay for their rewards and cash back. 

The simplest option is to just raise prices 2-3% across the board, if that's possible.