I remember that in part of modding the Wii, one of the tools asked if you were going to use the tool to play backups. I took it literally; my plan was to rip my game disks and run them from a USB drive. I answered "yes"...and the tool spit up a message against piracy, and set a flag somewhere in the NAND of the Wii.
I don't remember exactly how I fixed it...I think there was some undocumented way to clear the flag that you could only find by reading the tool's source. It was a good reminder of how much stupid, blind trust I tend to put into random tools from the internet.
