How do I subscribe to a Forum/Topic? I have several Forum/Topics that show up on my sidebar, which I can rearrange off the Configure Sidebar link. But I'll be danged if I can figure out how to add any more Topics to this list. I just realized that there is a "tech-news" Topic/Forum that seems to overlap with the "computers-chat" Topic/Forum, and I'd like to add it to my sidebar. But I can't figure out how to do that.