Do you shudder at the thought of entering a Blackberry-free zone?

Consider this 1987 Newsweek article:

What can diplomats do to keep their communications secure? They can trade in their Selectrics for manual typewriters, which don't emit buggable signals. They can banish computer-controlled telephones, which can be programmed remotely to pick up all sounds in the room just like a live microphone. An entire embassy-or key rooms-could be shielded with copper to keep electromagnetic signals from reaching listening posts. But in this day and age, it's virtually impossible to function without computers, and it's immensely difficult and expensive to ferret out sophisticated electronic ears planted in walls. Unless the debuggers make technological breakthroughs of their own, diplomats may have to get used to Magic Slates.

There are alternatives, of course:

The Battle of the Bugs