The legality, and even the exact definition, of IP is not black and white and comes up all the time in copyright discussions. If we want to say that the NDA states that your brain while at this company is ours and must be wiped if you leave, uh what? I think the spirit of an NDA is more that you don't release private information about the company.

I look forward to the day I can add inventions to that one field that asks for them upon being hired!