Is that not what one of the ideas behind Miiverse is? Do something awesome, tell the Wii U world. See the comment and try to beat or replicate it. I think Miiverse will give us the ability to post our own unique achievements and challenges. Just think of how many awesome ideas you can think of. Rave about something amazing or humorous you accomplished or Challenge the world to beat your time, total, or goal! This to me makes Achievements Unlimited!