How do I show the last saved date in an Excel worksheet?

Here's one that i like to use. It's not actually what you asked for though, this will put the info in the status bar on the bottom. if it's too long, you can cut out the time or username or whatever else.

Private Sub Workbook_BeforeSave(ByVal SaveAsUI As Boolean, Cancel As Boolean)
SaveStamp
End Sub

Private Sub Workbook_Deactivate()
Application.StatusBar = False
End Sub

Sub SaveStamp()
Application.StatusBar = "Last Saved on " & Date & " at " & Time & " by " & Application.UserName
End Sub