Inverted KVM: Control two PCs with one keyboard/mouse AT THE SAME TIME
 

We all know KVM switches, you switch between two systems and control them with one keyb/mouse.
I've been looking for a device which splits my keyb/mouse signal to two PCs which sends the same commands to both PCs at the same time.

I got this far:

anybody got an USB to try this out with?

this is an A-A USB Cable

Electronically, if you hook up one mouse to two different USB ports just by copying the USB cable, how do you make sure you don't have the PC USB ports connected with each other instead?

Like PC-mouse-PC results in PC-PC because the same solder islands are used. What you are searching for is a device which reads the data and copies it via an IC. Might be possible to build by hand, but requires some search for the right components. Maybe by using octo couplers.

such a device should exist somewhere, the request is not "out of this world"

It'll be very hard to find something like this because there hardly is any market for this (maybe there is, but it's not demanding this yet).
USB hub thingy sounds impossible because no resources are shared between the different A-ports (only between the A-ports and the B-port that connects to your pc).

What you might consider is taking 2 mice and keyboards and combine them into a single device, won't be easy tough because of timing problems and collisions.

other solution I've read is using wireless keyboard/mice and syncing them with two receivers to each PC at the same channel.

Just out of curiosity ... why ? :-p

Because he's MAD |D

because I want to control two PCs at the same time:) play 2 games at the same time with identical input to recreate the same gameplay path on both machines

You are weird jmke :D

Probably for review usage ?

of course:)