Online Financial Tools

I've been putting off signing up for a one-size fits all online financial tool like Mint or Wesabe. Have any of you dummies used one of these and had noteworthy experiences?

I suppose there's always the security risks of putting all your financial information in one place, but once a sketchy Panamanian waiter takes your Amex out of site to settle your tab/order his new Segway Skateboard, why sweat the small stuff?