CTRL-button and/or flags for selecting files and folders

[Guyver]

It would be great to have a button on the toolbar with a function of CTRL-Key. It could be a checkbox-button, or button like others. If it pressed, then CTRL-button is active, and you can select files and folders you need with some click (without to use a keyboard), if not, than CTRL-button is deactivated and filemanager works as normal. It would be also nice to have a flags left from the files and folders also for selecting them.

Example:

[Guyver]

Or another solution: simulation of CTRL+Left Mouse Click (single selection/deselection of files) with a Middle Mouse Button. I have seen it by Directory Opus. I think, it's a great future and should be implemented.