Probably. The only other one was Wolf's Rain, and I know that doesn't involve ninja or funk. (Actually, Samurai Champloo involves samurais and hip-hop, but it's close enough.)
That reminds me: They were able to continue the series, so I need to pick back up on it.
Rosalina: But you didn't.
Robert: But I DON'T.
Rosalina: You sure that's right?
Robert: I was going to HAVE told you they'd come?
Rosalina: No.
Robert: The subjunctive?
Rosalina: That's not the subjunctive.
Robert: I don't think the syntax has been invented yet.
Rosalina: It would have had to have had been.
Robert: Had to have...had...been? That can't be right.