As part of an article about the top 10 usability highs of Mac OS X, Juul Coolen has noted that even kernel panics looks nice:

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A funny but still nice example of Apple’s attention to detail. On the rare occasions when Mac crashes, it still does so in a respectable manner. Usability-wise it’s not perfect, since it doesn’t let the user know what went wrong and only asks the user to reboot the system. Still, beautiful and elegant.
Read more here: Top 10 Usability Highs Of Mac OS | Events | Smashing Magazine