I received this little gadget last week and it can tranform your old, traditional USB mouse and keyboard into a bluetooth device!
It is called the Nulaxy Keyboard & Mouse Wireless Adapter. It is capable to plug in 2 USB devices at the same time. The device is powered by either 2x AAA battery, or direct power from the Micro USB port.
Simply turn it on by the power button, press-and-hold the Pair button as soon as you see it flashing between red and blue, your PC or Mac will be able to detect and connect as a bluetooth keyboard or mouse. And you are good to go!
I have shot a short video below to showcase on how it works. Hope you enjoy it!