→ @kensanata points to my Identi.ca account!
Weird. I just discovered a Skype API Plugin for Pidgin/libpurple/Adium. It doesn’t really speak Skype: It requires Skype to be running in order to interface with it, apparently. Not quite what I was looking for, but I might give it a try anyway…
Update: I deinstalled it again because it required Skype to be running, and because chatting in Adium generated a duplicate chat window in Skype with the exact same content. I think I’d rather not use Skype on the Mac Mini where I don’t have a headset anyway!