It's a bit of an overkill, but I was intrigued to see CPFilms release its latest innovation this week, a special window film that is billed as blocking both WiFi and cellular signals.
The LLumar Signal Defense Film, as it's known, is a clear window film that blocks high frequency signals and ensures that WiFi signals stay in the building concerned.
Of course, being the cynical chap that I yam, I wonder if the WiFi signals can still leak out through doors and even brick walls, or am I just being picky?
Apparently the film has been a storming success with various US government departments, where it is also being used to reduce any glass damage in the event of bomb blasts.
Gulp - cheery stuff eh? I blame the US Department of Homeland Security myself...