Back in 2011 Microsoft opened their Garage and let out some software that enables you to control up to 4 PC’s from a single mouse and keyboard. Its called Mouse Without Borders and it’s very cool! Now they have updated it to support Windows 8.
Mouse Without Borders is a Microsoft Garage project by Truong Do. Garage projects are side projects that Microsoft employees like Truong build for fun on their nights and weekends. Mouse Without Borders was designed for people who use many computers in the same room. For example, a laptop or tablet that you take to meetings might sit right alongside the desktop PC in your office.
New in this release: Work better with Windows 8; Remote control from Windows Phone 7, Windows 8 tablet; New features and bug fixes.Download from here