PayPal.com is fast, safe, and easy, and it takes less than five minutes to sign up. It's recommended by the Wall Street Journal, Financial Times, and PC World. If you buy anything from a merchant with a Verified Account, PayPal guarantees your purchase against fraud. In addition, PayPal is simple whether you are paying bills or collecting them. You can accept online payments without a merchant account or even a Web site.
Best of all, it's FREE.
All you need is an existing debit/credit card and both parties in the transaction must have accounts with PayPal.