I'm sorry for my delayed response.
I was busy creating a post dedicated to this subject on
erikvandeven.com. But i have to many projects running at the moment so I don't have the time to finish the post.
So... If you havn't read
this post yet, then do it now :) It explains how to call posts with ajax... Then if you are a bit creative, you can combine that with checkboxes and jQuery AJAX.
I can't post my code, I'm sorry...