First heard at the "Legal Frontiers in Digital Media" conference here at Stanford:
It does not mean "of or pertaining to a Three Musketeers bar"--but "of little value." I suppose we did need a single word for that concept. So the word itself probably isn't, you know, nugatory. Time will tell.
At the conference I realized that I've never been in a room with 150 lawyers before. I'm rarely in a room with more than one lawyer; in the rooms I'm in, there are almost always zero. I'm pretty sure my colleague and I were the only ones cracking up and passing notes about "nugatory."