You can log in to SkiPresto.Com if you have a facebook account.
Click the "facebook" button on this page: -

A) If you are logged on to Facebook you will become logged-in to to this website (SkiPresto.com) too.
B) If you are not logged on to Facebook you will be offered a Facebook Login form. 
Then you will be logged-in to SkiPresto.com

Obviously, your facebook credentials remain secret between yourself and Facebook.  All SkiPresto receives is an "OK it's a valid Facebook Login, accept it".