[SalesForce] Accessing chatter user profile picture from sites

Just reading the other question you posted where your objective is to actually display the chatter photo on a vf page on the portal.

I read you went down this custom object route coz the Api route wasn't playing ball.

You can use the solution in the blog you mentioned (http://blogs.developerforce.com/developer-relations/2011/03/accessing-chatter-user-pics.html) even with a session id, you don't need an oauth token.

To get a sessionId all you need is a login call which you can obtain using the Ajax toolkit http://www.salesforce.com/us/developer/docs/ajax/index.htm

Here's a bit of sample code that fetches the photo at page load and redirects to the url

<apex:page>

<script src="../../soap/ajax/26.0/connection.js" type="text/javascript" />
<script type="text/javascript" >
window.onload = connectRemotely;

function connectRemotely(){
     var result = sforce.connection.login("USERNAME@DOMAIN.COM", "PASSWORD + SECURITY TOKEN");
     alert(result.sessionId);
     window.location.href = "https://c.XXX.content.force.com/profilephoto/USERID/F?oauth_token=" + result.sessionId;
     }
     </script>

</apex:page>

In addition to the suggestions by BritishBoyinDC, an easier way would be by inserting the entries from the public site into a custom object. Then have a scheduled class pick up the messages from the custom object and post for chatter feed. This, however, would not be real-time. The scheduled job at best can run once every hour.