I've always thought that the iPhone's lack of ringtone customization was no problem. A feature, even. All it takes is one jackass with a 50 Cent song as his ringtone to ruin the whole world for everyone else. (Obviously I am exaggerating for humorous effect. No one would ever actually do that.)
But the ringtones on KidRobot are so cool, I actually wish I could download a few.
Not hacking my iPhone, though.
Link: Kidrobot Mobile.