Time manipulator DCF77
This is not actually a time manipulator, but it is a DCF77 signal spoofer that is used to manipulate time on DCF77 synchronized clocks. DCF77 is a system that works on low frequencies and it constantly transmits real time clock information over 77.5kHz at 50kW from Frankfurt am Main.
So, here is a device that will "overwrite" the original DCF77 signal and force all clocks around it to synchronize to custom preset time and date. It has ~6W transmitter and is based on ATmega16.
You can see this device in operation in video after the break.