Anyone remember the cursed demo disc for PS2, where if you played the Viewtiful Joe demo with a memory card in, it'd wipe it? Yeah, that was a shared memory card between me, my brother and my mother. Hundreds of hours on Dynasty and Samurai Warriors, all the Battlefront and Final Fantasy data... So much progress, just... Gone. We didn't even know it would do it (obviously) and it took us so long to figure out why we lost all our data. Pissed*3.