One of my last tasks at Oddcast was to get a Facebook application out. Using our partner APIs, which allow us to add Voki to nearly any environment, we were able to build the app pretty quickly after I specced it out. You can create a Voki and send it to individual friends, broadcast it in your newsfeed or paste it to your profile.
So, given all the noise about how crowded Facebook is getting, if you want to make sure your friends really get the message, try using your own voice and a speaking character that looks like you, or a fish, or a robot, or whatever... Get the Voki Facebook app!