VisualDirSize 1.3 beta 6

VisualDirSize provide a graphical overview of the files/folders in a selected directory. You can view a chart by putting cursor on any directory and pressing 'Ctrl+Q'. Selected directory will be scanned and files/folders size will be displayed as a bar chart in the Quick View panel. Such bar chart is useful for showing the relative size of files/folders. For instance: you can quickly locate the biggest file/folder in directory.
Warning: Because the way how the plugin works, it's not recommended to use it on very big directories - delays might be pretty significant.