I just realized something quite funny.

If you have an application that has a save icon in the toolbar, odds are that it is an iconic representation of a floppy. Most people do not save things to floppies anymore on a modern system. An extension of this is that, on a Mac, the same convention is used in various applications, such as Microsoft Office for OS X, where the floppy icon used for save is present in the application running on a computer system which has not had a floppy drive for several years now.

The floppy, a proud contributor to interface cruft.

Now that it is established that floppies are (mostly) dead, what would be a better icon for a save button?