Apparently around half of American Millennials haven’t heard of The Hindenburg

[commasense]

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What computer icon most needs reworking?

This morning I was signing some forms in Adobe Acrobat, and I noticed that the icon I clicked on to do so was a fountain pen nib. Made me wonder, how many computer users under 40 have ever even SEEN a fountain pen? Of course there are the standard file cabinets/folders which have less and less relevance, and the snail mail envelope for email. What is your suggestion for the most archaic widely used computer icon, and what do you propose to replace it?