BugMeNot - BugMeNot is a free Internet service that provides usernames and passwords to allow users to bypass the registration process for websites.
One-Time Secret - One-Time Secret is a way to share sensitive information simple and secure.
ASP.NET SAML - ASP.NET SAML is an open-source authentication utility that has been used for exchanging authentication and authorization data between the channels.
Poof Links - Self-destructing urls for sending sensitive information.
DotNetOpenAuth - DotNetOpenAuth is a free-to-use compiled library that comes with the real support to your site visitor to login with the help of openIDs via getting control of the ASP.NET control onto the page.
nohistory.fyi - nohistory.fyi is free to use webservice to share secret messages in a secure way.