When you burn a disc in iPhoto or iTunes do you end up with the annoying “Untitled CD/DVD” in the sidebar of your Finder window? How do you remove it? There are several ways to address the issue.
First of all, by default, the sidebar of a Finder window and the elements contained therein are not permanent. Since the beginning of OS X, you could alter the order and contents of the sidebar by drag and drop. If you want your home folder to be first, drag it to the top of the list; if you want Applications first, same thing. If you want to remove these items, you should be able to simply drag them out of the sidebar, and like an icon from the dock, they should disappear in a cloud of smoke.
When the drag and drop does not work, maybe altering the Finder window and sidebar in Finder preferences is the way to go. In Finder Preferences, Sidebar, alterations are completed by checking or unchecking boxes.
Lastly, when these methods do not work, you can attempt to manually alter the preference list for the sidebar. (Warning—this is not for the squeamish!) In your Home folder, in the Library (hidden in Lion), there is a folder called Preferences. While there are 100s, if not 1000s, of individual plist files in the preferences, the one you want is called com.apple.sidebarlists.plist.
When opening the sidebar plist in TextEdit, each of the items, including the multiple disk aliases, has a discrete entry. Starting with the position line, OBB, ORR, etc., I carefully deleted each reference to the ‘Untitled Disk (number)’ from the plist file. After deleting the lines of information, I saved the document and restarted the computer. When next I opened a fresh Finder window, the offending entries were gone.