(MONEY Magazine) – Card companies are vying to be the Web currency of choice in two ways: beefed-up fraud protection and rewards. While the former is more hype than help, you could profit from the latter.

Visa and MasterCard have recently introduced zero liability on all of their credit cards. Previously, you could have been responsible for up to $50 of fraudulent charges. Now, no matter which bank issues your card or where you shop--online or off--you won't owe a cent. Many issuers, however, waived the $50 well before the policy switch. Even American Express historically hasn't made cardholders pay that $50.

What Web shopaholics should care about are cards that offer generous e-rewards or cash back for online shopping. Our favorite is the WebMiles MasterCard (www.webmilescard.com). For a $25 annual fee, you earn one point for each dollar you spend and extra points if you use the card at partners such as Borders.com or 1-800-Flowers.com. You can redeem points for plane tickets or discounts (8,000 points buys a $100 coupon) good on any airline, with no blackout dates. A bonus: If you shop online with the card and the merchant drops the price within three months, you'll be reimbursed for the difference. The current rate doesn't look too bad either: 2.9% for the first five months and 14.49% thereafter. --ADRIENNE CARTER