This mod adds an on-brand menu to the GameCube where you can play ROMs off of an SD card. The coolest part is that it piggybacks off of the disc drive instead of replacing it! And no soldering! I’m a big fan of passionate retromod projects like this.
Here’s the menu for anyone who can’t watch the video right now.
Looks great. I can’t see giving up my modded Wii for this, but if you’re only interested in GameCube games anyway it seems like a good solution.