Available as an assembled Module and as a DIY project.
No info about availability.
8-Channel switchable OR Combiner logic module
The Either-OR is an 8-channel switchable OR Combiner logic module. The Either-OR allows the user to switch between 2 signals per channel, or combine both of the channels for an OR logic output. There are also 2 jumpers per channel on the back of the module that allows the user to select between a center OR combiner or a center mute function, or ‘off.’ The Either-OR allows the user to combine gates, triggers and other logic signals into a single combined OR output. There are 8 numbered rows that can be daisy-chained in order to input many multiple logic sources, resulting in complex gate or trigger outputs.
This is a passive module and thus does not need a voltage connection or power cable. The passive diodes produce a slight voltage drop between the input and the output of each channel. As a gate combiner it will combine 2 gate inputs to produce an OR function on the output. When combining CVs the highest positive input will appear at the output with about 0.7 volts of drop.
http://www.synthrotek.com/products/modular-circuits/eurorack-either-or-module/
These merchants probably sell this module. Huh?