A new product from IT-11 (see http://www.it11audio.com) : active ABY Box.
My client ordered this to send his signal to 2 amps. Each output has its own JFET buffer to prevent loss of definition of the signal / sound (high impedance presented to the pedal board, low impedance output to amp : very usefull when long cables are used on stage).
And you know what ? Playing with 2 amps makes definitely pretty cool sounds !