nautilus
I have a horrible feeling that I am missing something very obvious, but here goes!
Nautilus has a handy context menu containing useful options like "Open in Terminal". Just right-click in an unused area of the window and select the option. My issue is what does one do if the window is full of files, as is often the case? In this case, the right-click menu I want is replaced with file options, and "Open in Terminal" is not available.
You have to install the nautilus-open-terminal package from the universe repositories for Ubuntu versions up to Ubuntu 15.04:
sudo apt-get install nautilus-open-terminal
If you want to install it with apturl, use this URL: apt://nautilus-open-terminal
Then:
nautilus -q
In order to restart Nautilus
In Ubuntu 15.10, the functionality is already included in nautilus!
To quickly get a file path in Nautilus we can use the right click context entry "Copy" to copy the file path to the clipboard.
Then just "Paste" (resp. "Paste Filenames") this path from the clipboard to the other application, e.g. a text editor.
Best Answer
Confirmed, clicking between the files should work in 18.04. Just make sure you right-click between the icons, not on the text below the icons. I'll try to get a screenshot.
Unfortunately, the screenshot seems to miss the context menu for some reason: perhaps because I was just capturing the current window. But where you see the pointer is where you need to right click to get the context menu.
Edit:
Alternatively, if you are in the list view and you have a right click key on your keyboard, you can simply hit that key on your keyboard directly after first opening the folder (no files yet selected). If there is a file selected, Ctrl+Space will unselect it.