Donavon wrote a gadget for Live.com, Spaces, and the Vista sidebar that counts down to when Vista officially ships to the general public. So I thought I would continue this using the Messenger Add-In APIs and write the same thing but for Messenger and have it display the countdown in your Personal Message area. Now, due to the limitations of the APIs themselves, I found no way to actually have the countdown flow like you would expect, but I have countered that by setting it so that whenever a message is received or sent, or your status is changed, it updates.
So: how do you add this add-in to Messenger? Well, there is no simple way at the moment, but I will give instructions on how to do this. First off, we need to tell Messenger that we want to be able to use Add-ins as Messenger by default doesn't have this option turned on. There is an entry in the Windows registry that we need to add, but for your ease I have a reg file that will do this for you. Just run this registry file and it will make the necessary changes; you will need to fully exit Messenger for this change to take effect.
