There is a solution to this! A simple app called 'Synergy' which is available on Windows, Mac and Linux, which basically makes one/many 'client' machines an extension of the 'server' screen real-estate.
It's trivial to install, download it, run it, and add the pi (or other machine) to the right, left, top or bottom of the screen in the server settings box. Click start, make a note of the IP address that it's configured to run on, and you're ready to accept connections.
On the Pi, install the software:
sudo apt-get update # get the latest version of software catalogue sudo apt-get install synergy
And run it:
synergyc {IP of server}
Move the mouse to the chosen side of the screen and it appears on the Pi. When you have done so, the keyboard is also attached virtually to the Pi - magic!