Windows only: Freeware application QT ToolBar adds quite a few file manipulation and filtering techniques to Windows Explorer. With QT ToolBar you can enter a specific file extension and select all similar files in bulk. Additionally, QT ToolBar adds a few buttons to the interface that will copy an entire path plus the file name to the clipboard and launch a command prompt in the directory. QT ToolBar's search feature is a bit tricky and doesn't appear to support wild cards so no need to put "*.mp3" in the search field. Similar to QT TabBar, QT ToolBar is a free download, requires .NET 2.0 and installs as a standalone executable (it won't show up in Add/Remove Programs). Alternatively, you can ditch Explorer altogether for Xplorer2. QT Toolbar's a free download for Windows only.