how to best approach making a matrix code "screensaver" in unity3d

and I mean "The Matrix" code

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Generally I would say that making a lot of cubes next to each other would do the trick. you would just switch textures of matrix aharacters on them, but having so much cubes really slows my pc down. what could be other possible approaches of dealing with so many "objects"/textures/characters that need to be laid down uniformly and appear in big quantity, so that it's more CPU-friendly?

could you post your solution please.