Sheath Strike

Use of a sword's sheath as a weapon. If you still have the Cool Sword, then you can wield them both, or just leave the sheath on to pack an extra punch. If someone is using the sheath instead of the blade, it may be because they aren't intending to kill their opponent. An Iaijutsu Practitioner may use the sheath as a primary weapon, for feinting or stunning, or to show that it's not yet time to get dangerous.

Anime and Manga

 * Rurouni Kenshin: Kenshin uses his sheath to land the finishing blow on Jin-E in their battle.
 * Hiko Seijuro XIII does use the "sheathed sword as a shield" version--then he draws, while still blocking, and absolutely pwns Kenshin.
 * Nameless of Sword of the Stranger refuses to draw his sword, making him this by default.
 * Inuyasha frequently uses the sheath of his Empathic Weapon Tessaiga as a shield, since being able to contain Tessaiga's power means the sheath is capable of generating a fairly powerful barrier. He's also made inventive use of the sheath's ability to call the sword into it on at least one occasion.
 * Bleach: when Ikkaku isn't fighting with shikai / Bankai, he dual wields his sword and sheath.
 * In Corsair, Canale, a former assassin now afraid of killing, is challenged to a duel and fights mostly with his sword sheathed as a result.
 * In Magical Girl Lyrical Nanoha, Signum will occasionally use her weapon's sheath to parry attacks. She can also combine her sword with the sheath to transform it into a bow.
 * Kanda from D Gray Man when he gets serious.
 * In Digimon Xros Wars, the Bagra Army general Tactimon used a sheathed sword (Which he never unsheathes) to fight the good guys.

Comic Books

 * In Usagi Yojimbo, Genosuké the bounty hunter dual wields his katana and scabbard from time to time. However, that seems to be more a result of him always casually carrying his sword dangling over his shoulder, rather than a specific technique. Since he never tucks the sword into his belt in the conventional manner, he has to keep the scabbard in his off hand even with the sword drawn. After meeting Gen, Usagi uses the same technique occasionally. He also uses his scabbard to beat sense into idiots who don't deserve to die.

Film

 * O-Ren Ishii briefly dual wields her sword and sheath at the beginning of her fight with Beatrix in Kill Bill.
 * The So Bad It's Good film Blood and Bone has the hero, Bone, fight the Big Bad in front of the Bigger Bad. The Big Bad being armed with a sword, the Bigger Bad has his henchmen give him one as well. The Hero just throws away the sword and fights with the sheath.
 * House of Flying Daggers: Mei manages to defend herself rather well against 4 mounted spear men using only a sword scabbard for a weapon while.

Literature

 * Sam Vimes pulls it off with panache in Night Watch.

Live Action TV

 * This shows up occasionally in Super Sentai and Power Rangers. Interestingly, many of the characters who do this are samurai:
 * In Ninja Sentai Kakuranger and Mighty Morphin Power Rangers Season 3, when Ninjaman/Ninjor grows to Humongous Mecha size and transforms (into "Samuraiman" in the former), he connects his sword to its sheath and makes a javelin out of it.
 * ShinkenGold/the Gold Samurai Ranger does this in keeping with being an Iaijutsu Practitioner.
 * Shurikenger's sword has an extra-wide sheath, all the better to use as a baseball bat. Ironically, while his American counterpart is identified as a samurai this use of the sheath is edited out.
 * A couple others (Black Knight/Magna Defender and the Hurricangers/Wind Ninja Rangers) have it set up so their sheathed swords can be used as laser rifles.

Tabletop Games

 * One of the Swordsman Schools in Seventh Sea teaches the use of the scabbard as an offhand weapon.
 * In GURPS: Low-Tech and Martial Arts scabbards can be reinforced to use as a baton. Special designed sheaths can even be turned into a blowpipe.

Video Games

 * Vergil in Devil May Cry does this as the first two strikes of his main combo, and does it to Dante during a cutscene.
 * Afro Samurai often uses his sheath as a weapon as well, particularly in the videogame where most of your combos involve a combination of sheath-strikes and cuts - and some of the niftier finishers involved steadying your opponent with the sheath to launch a pin-point strike through his skull.
 * Ukyo's "weak" attacks in Samurai Shodown have him jabbing with his scabbard, keeping his sword sheathed.
 * The Ronin's Sayageki ability in Etrian Odyssey 2 Heroes of Lagaard.
 * Mitsunari in Sengoku Basara uses his sheathed sword against opponents he doesn't want to kill, such as knocking Kanbe unconscious by hitting him in the face with it.
 * In the Anime of the Game, Sasuke dual-wields with a sword and sheath when caught off guard by another ninja.
 * Occasionally done by Zhou Tai as a juggling attack in the various Dynasty Warriors and Warriors Orochi games where he is given a katana. Then again, he's one of maybe two characters to even have a scabbard in the first place.
 * Guy from Tales of the Abyss does this as part of his fighting style.
 * Same for Asbel from Tales of Graces, as part of his alpha arte moveset.

Web Comics

 * No Need for Bushido uses this, combined with Calling Your Attacks.