Although patents don't always point to final products, a freshly published Sony patent points to an interesting possible design for the PS4.
As spotted by The Sixth Axis, the new hybrid design combines the traditional Dualshock controller with the Move motion controller.
Diagrams show a fairly conventional joypad that has the capacity to split into two separate units, thus mimicking the twin Move/Navi controller setup used for some PlayStation Move titles.
There is another key difference, of course – both halves of the controller have a Move-style light-up Orb attached to the top. All of Move's required components such as the magnetometer, accelerometer and gyro are housed within the traditional casing.
The patent was actually filed back in May 2011 so it's impossible to say that it's definitely a PS4 device, although it seems likely.
Certainly any method that removed the necessity to invest in additional controllers to play Sony's motion titles would certainly help the technology's adaptation amongst traditional audiences.