We don't have fax where I work anymore. If I need to send a scanned document, I need to go to the Multi-function machine, insert and authenticate my credential, scan the document to an email (the machine will only email the user making the scan, nobody else). Once complete, I remove my document and credential, go back to my desk and retrieve the document from the email from the scanner and then email it to whomever needs it. Of course our system is a bit more secure than most email systems, we have end to end encryption that allows us to protect sensitive information better than fax.
Wait? How does fax protect sensitive information?
It doesn't, what improves the security of fax is the fact that there is a limited opportunity for interception. With email, the message is stored as it is forwarded, but with fax, the only time the message can be intercepted is during transmission, unless a recorder is attached to the telephone line (or the packets are logged with VoIP).
Every so often at work I get the "what's your fax number" question, I just say we don't have one because the only person I've seen use it curses like a maniac whenever she goes near the thing.