This week's CEATEC technology show just outside Tokyo is home to not just the latest mainstream gadgets, but also some of the weirdest tech you'll ever come across.
In the latter category we have a mobile phone application that is supposed to let users see through walls.
The 'Real Space See-through Mobile' software comes from KDDI's R&D laboratory and Tokyo University and is – you'll not be surprised to learn – still just a prototype.
Although we weren't able to see it in action, we can tell you that it is supposed to be able to judge its surroundings, including those on the other side of a wall, using six different sensors.
Three acceleration sensors combine with a similar number of geomagnetic sensors and a GPS chip to work out exactly where the phone is and in what direction it's pointing.
Using some sort of digital voodoo, the software then uses OpenGL to draw on the screen what it has 'sensed' is in the immediate surroundings.
Better yet (we think), it also has the ability to work out whether the user is walking, running or in a vehicle and calculate calories burned in doing so.
We're told it even uses the phone's microphone to work that one out, although quite why the engineers bothered, we're still pretty much clueless.