We have Sharepoint 2010 installed with MySites setup, allowing our users to upload their own profile picture. This seems to work great, however when we start using things like Discussion lists on another web application inside the farm (and in a different site collection), whenever a user's profile picture is displayed, it's asking us to authenticate. Some browsers handle this a bit more gracefully (chrome only asks the first time content is requested from the mysite web application), but IE asks for EVERY single resource (picture) from that web application.
We are using basic auth (so that users don't have to type in the domain part of their username - big problem for us) over HTTPS.
Is there a better way to 'share' authentication between these two web apps / site collections so that users are authenticated automatically on their MySite after they sign into the other web app (our intranet in this case)? I'm open to things like switching to Forms based authentication, etc.