I just found out that you could run pico-8 games with fake-08 which is really cool! Other things I've done include using Tiny VNC to stream a desktop and EasyRPG player for RPG Maker 2000/2003. I've also seen someone install linux at one point.
What other cool or underrated things you could do on a homebrewed 3DS besides the usual play 3DS/DS/GBA games for free?
Doesn’t matter if it's not enforced. We have no holding phone rules in GA and I routinely see people using their phones while driving.