Sometimes the feature that attracts you to a Web site isn't the same as the feature that keeps you coming back. That's been my experience with PayPal.com (www.paypal.com).
Does the following sound familiar? A friend says, "If you pick me up some lunch, I'll pay you when you get back." Or, "Let's go to a movie; you buy the tickets, and I'll pay you later." How many times have you had to remind those friends that they owe you money?
PayPal was designed to make sending money (or requesting payment) as fast and easy as sending email. You enter your name, street address, email address, credit-card information, and an amount that you owe. Then PayPal charges your credit card and notifies the payee via email about your payment.
It's a great idea, although cashing in can be a bit of a challenge.
Over the long term, PayPal's "killer app" may have nothing to do with movie tickets. PayPal offers an incredibly convenient way to pay for stuff that you buy through Web-based auctions. As much as I love finding stuff on eBay, I loathe sending money orders or cashier's checks. And, as more and more sellers get comfortable with PayPal, I'll get more comfortable with spending time at auction sites -- and I'll spend less time buying movie tickets for my friends.