Things I've suggested that have not been received well in my classes:

• If your boss asks what you think of your counterpart at the company you're about to acquire, and he's as good as or better than you, you have a responsibility to say that instead of subtly undermining the new guy.
• Salary transparency within an organization. Everyone knows what everyone else is making. This one got a really vehement "That just isn't DONE!" reaction.
• When are accounting principles going to get completely overhauled to recognize the non-fungible importance of people and information? Or at least the fuzziness of the line between cost of goods sold and operating expenses in knowledge industries?
• Sumana: Practicing our defense speeches would make them better! So I'm holding a practice session.
  Other People: Great! Good idea!
  Sumana: I mean, yeah, no one's presentation will be perfect when we practice, but even if you just have a fraction of a proto-speech, no slides, it's better to try it out in front of people and get feedback early. Fail faster. Rapid prototyping. Agile. Stop procrastinating and get some small useful bit of work done on it right away and start improving!
  Other people: Absolutely. Glad you're putting it on. Great idea.
  Sumana: So you're coming, right?
  Other people: Ehhh, it's not ready yet.