Maybe when something comes along to replace "save"?

With the steadily increasing amount of software that auto-saves without you noticing, maybe soon we just wont need to "save" anything. It'll just happen.

GNOME has been using a picture of a hard drive for quite a while now: http://commons.wikimedia.org/wiki/File:Gnome-document-save.s...

Though that may also become antiquated with SSDs and cloud storage :-)

My guess is never. The universal train icon for signs has a funnel and a cow-catcher, and it's a long time since a train looked anything like that.

Same goes for the universal sign for telephone - nothing like a modern cordless handset.

We can already seen this in action as the icon for 'mp3' on signs looks like a first-gen ipod. Already no players (even ipods) look like that, but I think it will stick around for a long time.

Some things get stuck as icons and the original meaning is lost with the sands of time. Once the icon is assigned to a meaning for most people, it sticks. There's no reason to update the icon, even if it no longer represents the object, because everyone agrees on the meaning.

There's only a handful of apps on iOS that include a save button, and even of those that do include one, DocsToGo is the only one I can think of that uses a floppy for a save icon. It might be gone before you know it ... though I'd guess you'll still see it in Windows in 2020 or beyond ;)