Ranma ½: Tendou-ke no Oyobidenai Yatsura!

This features a Nabiki narrated review of the series where she discusses various characters that the Tendo family has had to tolerate spliced with new animation of Nabiki hanging around the house, taking a bath, and wondering about the true identity of P-chan. It was available through the Kitty Animation Circle.

(Source: furinkan.com/ranma/anime/specials.html)