Question: I'm implementing a SAML 2.0 Service Provider and need to install a SAML 2.0 Identity Provider for testing. Given this need, the Identity Provider should ideally be free (or have a trial period) and be easy to set up and configure.

I'm looking for basic single sign on and single log out functionality.

I've tried Sun Opensso Enterprise. The price is right, but so far it's been a nightmare to configure. Also, its error messaging and logging leaves a lot to be desired and I'm often troubleshooting an issue that basically boils down to a misconfiguration or a counterintuitive default setting.

Answer: 
You can configure [Auth0](https://auth0.com) as a SAML IdP. The setup [is straight-forward](https://auth0.com/docs/protocols/saml/saml-idp-generic) and there's a free tier available.
For testing [Mock SAML](https://mocksaml.com) or [SAMLTest](https://samltest.id) are good options to get started. Also Okta with their free developer account.