Weird thought...

feorag said something about modems, which made me wonder; If a spy wanted a secure communications route, and didn't mind using phone lines, would an old-fashioned modem now be better than e.g. WiFi and the other common ways to send email? Sure as hell nobody who wasn't prepared would be expecting it or these days, and a lot of older laptops still have built-in modems. A bit slow by modern communications standards, but you can send several thousand words in a second or two, so not that bad.