I have a two computers on my desk that I use regularly. My desktop, which is my main computer, and a laptop. Whenever I'm doing work on both, burning CDs, downloading updates, etc., I find it a pain to switch between a mouse and a full-size keyboard to a trackpad and mini-keyboard.
Thankfully, there is a program that solved my dilemma. The solution I found is an open source project named Synergy (http://synergy2.sourceforge.net/). It even lets you share between computers with different operating systems, so you could share the same mouse and keyboard between computers running Windows, Linux, and a Mac. [more]
From the Synergy website:
Synergy lets you easily share a single mouse and keyboard between multiple computers with different operating systems, each with its own display, without special hardware. It's intended for users with multiple computers on their desk since each system uses its own monitor(s).
Redirecting the mouse and keyboard is as simple as moving the mouse off the edge of your screen. Synergy also merges the clipboards of all the systems into one, allowing cut-and-paste between systems. Furthermore, it synchronizes screen savers so they all start and stop together and, if screen locking is enabled, only one screen requires a password to unlock them all. Learn more about how it works.