title: Web Service Authentication using OpenID
body: <p>I'm going to be developing a REST-ful Web Service for a new public website. The idea behind the web service is to have 3rd parties develop fully functional UIs for the business logic.</p>
  
  <p>For security reasons, I'd like to avoid users having to give their passwords for our service to the 3rd party applications. (Perhaps this shouldn't be a big concern?) Instead, I'm looking to implement some sort of login system on our site that provides an auth token to the 3rd party app but keeps the actual password out of their hands.</p>
  
  <p>This made me think that OpenID might be a potential solution here. It seems to me that it should work: the actual password is handled by the OpenID provider and so it doesn't rest with the 3rd party app. I think that the trouble would probably lie with the various passthroughs, but that should be manageable.</p>
  
  <p>However, there's a surprising lack of Googleable info on this, so I'd like SO's opinion. Has anyone implemented a similar system before? Is it even possible? Is it worth the trouble?</p>