OpenID is a standard that allows users to be authenticated in a decentralized manner. OpenID enables user to be identified across the internet using a single unified OpenID identifier (or account).
However some websites (particularly blog and forums) insist users to login in order to leave a short comment or remarks which sometimes is not convenient for some users that value anonymity.
The OpenID Anonymity service is an OpenID provider that helps you get around website or application that requires OpenID login. To use OpenID Anonymity service, the user only need to key in its URL Identifier – http://openid.anonymity.com/some_random_id and the user will be automatically authenticated, without the need to log-in or to enter password, which is very convenient if one needs to be anonymous.
p/s: Additionally here’s a collection of Public Domain OpenID (tangofied) icons, created by Jakub Szypulka
OpenID is a standard that allows you to log into many websites or services using a single identity as oppose to memorize several different username and password on different websites.
Websites that provide OpenID identity are called OpenID providers. There are many OpenID providers, and one of it is Launchpad. Launchpad users can use their Launchpad account URL as OpenID URL in order to access OpenID-supported websites or services.
For example :
The general form of Launchpad OpenID URL is: https://launchpad.net/~your_user_name.
Where I can use OpenID for authentication?
You can use your Launchpad URL for authentication at websites or services that feature OpenID logo. Examples of such services is Blogger comment form, Sourceforge and Facebook.
How to use Launchpad account as OpenID provider?
On website that supports OpenID, enter your Launchpad account url : https://launchpad.net/~your_user_name, replace your_user_name to your own username. Then, you will be directed to your launchpad account, enter your password and you will be automatically authenticated for the current service.
Screenshot example :
The favorable side-effect of using your Launchpad account as OpenID is that you can indirectly promote (and probably brag) about your contribution (aka karma) towards Ubuntu.