I had enough to switch between windows to work on external files.
So, here is ExternalTools
It adds some commands to the File Browser, allowing one to edit in the $EDITOR (for me this is gvim) and another thing for opening the file externally through xdg-open (which kind of opens about anything).
Basically, one can extend this to whatever is needed.
The only thing is that FileServices initialize needs to be called when a new service is added if you create your own.
This is Unix only and requires OSProcess to be loaded (use the ConfigurationBrowser).
Gofer it
url: 'http://www.smalltalkhub.com/mc/philippeback/HOExtras/main';
package: 'HighOctane-Tools';
load.