What a lovely surprise: I turned on Paper Mario: The Thousand-Year Door a few minutes ago only to see tht my first save file, nearly- complete with Mario at level 86 and with every single enemy tattled, recipe made and badge collected, has been inexplicably corrupted. The file's name has been replaced with the phrase "File corrupted", and its progress now says "This file must be erased". I hadn't shut off the game while it was saving or loading, and I had already established that maxing out the in-game timer at 99:59 didn't translate to any ill effects.
I've yet to see whether the same sad fate has befallen any of my other Gamecube titles, and I'm currently afriad to know. Any ideas? Can the memory somehow be retrieved, perhaps?...