Ask HN: What are the most memorable code comments you've encountered?

Most of the code bases I've worked in haven't been well documented. In the few that have been, most of the comments have simply stated the obvious. Maybe once or twice a year I'll run into a gem.

What comments have you stumbled on to that are most memorable for you? For whatever reason - maybe they were insightful, maybe they made you empathize with the poor engineer(s) who came before, or maybe because it was past you who wrote it and you completely forgot about it.