USB-845-KM-BC "MegaCast"™ 5 Port USB Keyboard & Mouse Multicaster looks like a sweet product and i would be tempted to get one for when i finally hit the full hardware route.

the one addition i would like to see would be some kind of mute feature (like in Keyclone). say you had 5 buttons on the device and you could select which outputs would recieve the keystrokes by enabling the buttons.