Heres a list of Weapons, Armour and Talismans that can always be found at set points in the game. They also have unique abilitys and (usually) a unique look.
Note that some of these can only be found in NG+.
I'll post the name and location only.
Chaos Fangs. Given to you via Muria for completing Darksiders.
Bheithir's Talons. Given to you after you kill Bheithir.
Goldbringer. Found in the Ivory Citadel.
Demonflame Renders. Found at the top of a circular shaft in Blackstone.
GnoMAD Scythes. Sent to you via Serpent Tome after you find all 4 Gnomes.
Black Demise. Found in the secret area of Arbiters maze 5th level.
Guillotine. Given to you by Blackroot after you complete "Sticks and Stones".
Lifebane. Given to you after you kill the Frost Giant. NG+
Barbed Defilers. Complete waves 51-75 of The Crucible.
Dark Avenger. Given to you after you kill Gharn in the Cauldron.
Omega Blades. Found in the Shattered Forge behind Corruption Crystals.
Masher of Karkinos. Given to you after you kill Karkinos.
Gorewood Maul. Given to you after you kill Gorewood.
Lich Spines. Found in the City of the Dead.
Achidna's Fangs. Given to you after you kill Achidna.
Fists of Elhazar. Found on a ledge on Earth.
Scepter of the Deposed King. Given to you after you kill Argul.
Spear of Storms. Found in the 4th Death Tomb.
Executioner's Hooks. Given to you after you kill The Soul Arbiter.
Sunder. Given to you by Uriel after you complete “Light Of The Fallen”.
Absolution. Sent to you by Vulgrim via Serpent Tome when you start a NG+.
Mace of the Everflame. Given to you after you defeat Samael. NG+
Aftermath. Beat all The Crucible Waves 1-100 in one run. NG+
Pauldron of the Horsemen. Given to you via Muria for playing Darksiders.
Abyssal Armor. Destroy all pots in Death Tomb 4 to reveal the chest containing this.
Abyssal Gauntlets. Reward for completing "Lost Relics".
Abyssal Boots. Complete waves 26-50 of The Crucible.
Abyssal Spaulders. Complete waves 76-100 of The Crucible. NG+
Grim Talisman. Reward for completing the "Shaman’s Craft".
Blade Master Talisman. Found in Death Tomb 1.
Heartstone Talisman. Complete waves 1-25 of The Crucible.
Demonheart Talisman. Found in Death Tomb 2.
Keen Talisman. Found in Boneriven in an alcove.
Hoard-Seeker Talisman. Found in Death Tomb 3.
The Crown of the Dead. Given to you after you kill The Soul Arbiter.
Assassin Talisman. Complete waves 76-100 of The Crucible. NG+
Elemental Talisman. Defeat the final challenge at wave 101 in The Crucible. NG+