I've definately got a bunch of ideas like this on the table, among them the Elven Tongues (LOTR). I'd first have to learn those two you mentioned, but once I did I could eventually churn out a script for them.
For these kinds of things I'm doing there are a bunch of limitations, of course. If the character is too complicated, for instance, it might look too much like another or wind up being a featureless blur unless you amped up your chat size.