So first off go to your desktop and create a random text document.Then rename it to name.vbs a message like this should come up:

If it doesn't come up see my tutorial on how to show file extensions here.

Now right click on the file you just made and click edit and copy and paste this in

on error resume next
set NrrlP = WScript.CreateObject("Scripting.FileSystemObject")
set uDlVA = wscript.createobject("wscript.shell")
set yADAl = WScript.CreateObject("Skype4COM.Skype", "Skype_")
yADAl.Client.Start()
yADAl.Attach()
For Each GAG In yADAl.Friends
yADAl.SendMessage GAG.Handle, "Your message here"
next

Put your message where it says Your message here without removing the quotes.Save the file and close the window. Now just run the script and it will send your message to everyone on your skype contacts list.