Negative Margins, Hack or Not?

I've come across various posts where people are stating that negative margins are hacks. Thus I've strayed away from using them with 开发者_运维问答exception to particular cases when I can justifiably use them, like throwing text off the screen with margin:-9999px

Question, are negative margins a hack and when is it right to use negative margins? I've seen them used in the 960 Grid System with, .push and .pull, any other cases where they are justifiably usable?!?!

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Negative margins are allowed based on W3C specifications. I have used them to let things overhang their container.

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I would argue it's not a hack: It's defined, logical behaviour; it's supported in all browsers; it can be expected to be supported in future versions of browsers (the absence of future support is the most important argument against hacks).

Also, as @durilai points out, they are officially sanctioned (although with limits) by the W3C.

This Smashing Magazine article supports the case.

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I suspect they've been labeled as a hack because of inconsistent browser behavior.

Whenever possible I use position: relative and negative top and left values to pull elements into new locations. This isn't possible for every case, but I find it behaves more consistently in all the Internet Explorer flavors.