Skies of Arcadia Hard Mode -by Tortigar
Pokemon XG : NeXt Gen -by StarsMmd
I tested both hacks and they work on both Nintendont and Dolphin. Played through the whole of the SoA Hard Mode hack. Good stuff.
I was also wondering if you guys know of any other extensive Gamecube hacks like these. Those are the only two I've found searching the internet, and the Gamecube hacks section here on the site is quite slim.