Arduino is great for simple projects as long as special capabilities aren’t required. You can find a suitable shield for specific tasks like driving motors, LCDs, or connecting to the internet in most cases. But what if you need to drive a LED cube. Driving 8x8x8 cube becomes challenging and require a few shift registers to expand the number of I/Os.
Obviously, for Arduino, a shield is needed. Connor has designed a voxel shield that makes it easy to drive cubes with up to 512 LEDs. Or LED matrixes in particular cases. In his design, he used 9 SN74LS595N shift registers. As LED cubes require a significant amount of power, he added a connector that can suck the power from ATX power supply. So great addition to Arduino shield pool.