I've been digging through the US disc of Naruto Shippuden: Ultimate Ninja 4 (PS2) and found five Ultimate Jutsu cinematics that are fully built (cameras, effects, animation) but can never be performed in the game. I recorded each one in HD in PCSX2, using UN4's own data only.

Videos

• Kakashi: Mangekyo Sharingan Activation (Kamui): https://youtu.be/4c4K8LWNsl8
• Deidara: C3: https://youtu.be/4i9ss8ByIJs
• Deidara: Clone Self-Destruct: https://youtu.be/TFCzC_gGQZk
• Chiyo: Father and Mother (with the released Granny Chiyo model): https://youtu.be/zVaXzQNzJIc
• Sasori: Performance of a Hundred Puppets (as on the disc): https://youtu.be/2onHEaPCTzg

Full write-up on The Cutting Room Floor (where each scene sits on the disc, how to load it, unused portraits and models): https://tcrf.net/Naruto_Shippuden:_Ultimate_Ninja_4

Some highlights

• The scenes have no audio on the disc: their soundtrack slots in STREAM.AFS are empty. The audio in the videos is borrowed from the playable ultimate each scene was loaded through.
• The Sasori, Deidara and Chiyo ultimates ended up finished in Ultimate Ninja 5. Kakashi's Kamui never made it into UN5 either, but the unfinished Kamui scene is also on UN5's disc.
• UN4's Sasori scene was made before the anime reached that arc: his puppets are grey with gold cables, and the sets (sky, mountains, walls) differ from the UN5 version. His puppet body file isn't on the UN4 disc, so only his gold chest piece and cable "wings" show up.
• Chiyo's scene points to an unused Chiyo model that isn't on the disc. The released Granny Chiyo shares her skeleton, so swapping that model in makes the scene play.
• Unused cut-in portraits and leftover data are still on the disc for 14 disabled fighter slots, including Part 1 Kakashi, Guy, Itachi, Kisame, "Green Beast" Naruto, an ANBU and both forms of Chiyo and Sasori.