I recently got setup at home with three identical monitors as I work from home often. Here's a picture of them. The left-most monitor is my main monitor for my work laptop. I extend that desktop to the middle monitor. The right-most monitor is for my home computer. For productivity and neatness reasons, I wanted to use only one mouse and one keyboard for both my work laptop and my home computer.
There are many tools out there that allow you to use one keyboard and one mouse with multiple computers, but most of them require special hardware and aren't free. It was recommended that I try Synergy, since it was free and only required software to be installed. I wasn't sure if it would work when I was VPN'ed into work as it doesn't work across my husband's work VPN, but I gave it a try anyway. Luckily it worked great for me. By adding four links to the server, I'm able to move the mouse 360 degrees in either direction. There is a very short delay when moving the mouse between computers, however it is not noticeable to me.
If you are using multiple computers with different monitors and don't already have a solution to the one keyboard and one mouse problem, then I'd highly recommend using Synergy.