You can get any topic within any forum as a sidebar though.
Go to the latest posts page for the forum that contains the topic you want. Click the topics link at the top of the page. Click whatever topic you want as a sidebar. Directly above the first article listed, you will see the following:
"You do not subscribe to this topic. Click here to subscribe."
Click it, and you have a sidebar.
To get rid of a particular sidebar, use the same method to get to the topic. This time you will see the following:
"You subscribe to this topic. Click here to unsubscribe."
Click it, and it is no longer a sidebar.
When you have which topics you want as sidebars set up as sidebars, you can use this link, which you get to by clicking on your name in the upper right of the latest posts page and then on "My Subscriptions", to set the order in which they appear from top to bottom, how many articles are in each individual one, and what color they are.
Thanks, LM