[mikeash]

Not JSON, but here's a truly horrible example of Internet Explorer using specially formed comments to take different actions: http://www.quirksmode.org/css/condcom.html

[devicenull]

They really aren't that bad, definitely very handy for injecting IE specific stylesheets, without having to rely on javascript.

[mikeash]

I'm sure they're handy, but just crashingly inelegant.

[chris_wot]

Not to mention that the only reason for needing IE specific stylesheets is because IE doesn't follow CSS standards properly!!!

[chris_wot]

Uh... this was downvoted because? Certainly not because it's wrong.