If im not wrong there are models that can be found in the World Editor by writing these paths:
Hiddens Doodads:
Ancient Ziggurat 1:
Doodads\Northrend\Structures\AncientZiggurat\AncientZiggurat0.mdl
Ancient Ziggurat 2:
Doodads\Northrend\Structures\AncientZiggurat\AncientZiggurat1.mdl
City Building 1:
Doodads\Cityscape\Structures\Morecitybuilding\MoreCitybuilding0.mdl
City Building 2:
Doodads\Cityscape\Structures\Morecitybuilding\MoreCitybuilding1.mdl
City Building 3:
Doodads\Cityscape\Structures\Morecitybuilding\MoreCitybuilding2.mdl
City Building 4:
Doodads\Cityscape\Structures\Morecitybuilding\MoreCitybuilding3.mdl
City Building 5:
Doodads\Cityscape\Structures\Morecitybuilding\MoreCitybuilding4.mdl
Grass Tuft 1:
Doodads\LordaeronSummer\Plants\GrassTuft\GrassTuft0.mdl
Grass Tuft 2:
Doodads\LordaeronSummer\Plants\GrassTuft\GrassTuft1.mdl
Grass Tuft 3:
Doodads\LordaeronSummer\Plants\GrassTuft\GrassTuft2.mdl
Grass Tuft 4:
Doodads\LordaeronSummer\Plants\GrassTuft\GrassTuft3.mdl
Larger Sign Post:
Doodads\LordaeronSummer\Props\Signpost\Signpost0.mdl
New City Bridge:
Doodads\LordaeronSummer\Structures\CityBridgeSmall\CityBridgeSmall.mdl
New Lordaeron Bridge:
Doodads\LordaeronSummer\Structures\LordaeronBridge\LordaeronBridge.mdl
New Wooden Bridge:
Doodads\LordaeronSummer\Structures\BridgeLog\BridgeLog.mdl
Rock Chunks 1:
Doodads\Terrain\G_RockChunks\G_RockChunks0.mdl
Rock Chunks 2:
Doodads\Terrain\G_RockChunks\G_RockChunks1.mdl
Rock Chunks 3:
Doodads\Terrain\G_RockChunks\G_RockChunks2.mdl
Rock Chunks 4:
Doodads\Terrain\G_RockChunks\G_RockChunks3.mdl
Rock Chunks 5:
Doodads\Terrain\G_RockChunks\G_RockChunks4.mdl
Rock Chunks 6:
Doodads\Terrain\G_RockChunks\G_RockChunks5.mdl
Hidden Effects:
Alternate Heal Target:
Abilities\Spells\Other\HealTarget2\HealTarget2.mdl
Alternate Hydra Impact:
Abilities\Weapons\HydraliskImpact\T_HydraliskImpact.mdl
Ballista Impact:
Abilities\Weapons\BallistaMissile\BallistaImpact.mdl
Ballista Target:
Abilities\Weapons\BallistaMissile\BallistaMissileTarget.mdl
Bersek Upside Down:
Abilities\Spells\Orc\TrollBerserk\HeadhunterWEAPONSRight.mdl
Bersek Target:
Abilities\Spells\Orc\Berserker\Berserkertarget.mdl
Blood Impact:
Abilities\Weapons\Blood\BloodImpact.mdl
Bloodlust Special:
Abilities\Spells\Orc\Bloodlust\BloodLustSpecial.mdl
Water of Corrupted Moon Well:
Abilities\Spells\NightElf\MoonWell\CorruptedMoonWellTarget.mdl
Demon Revive (looks like ordinary revive):
Abilities\Spells\Demon\ReviveDemon\ReviveDemon.mdl
Forked Lightning Target:
Abilities\Spells\Other\ForkedLightning\ForkedLightningTarget.mdl
Green Rings:
Abilities\Weapons\PoisonSting\Rings_Green.mdl
Green Smoke:
SharedModels\Smoke1_Green.mdl
Mark of Chaos:
Abilities\Spells\Human\MarkOfChaos\MarkOfChaosDone.mdl
Moving Feather:
SharedModels\Feather1.mdl
Night Elf Revive (looks like ordinary revive):
Abilities\Spells\NightElf\ReviveNightElf\ReviveNightElf.mdl
Obsidian Feather:
SharedModels\ObsidianFeather.mdl
Red Glow:
SharedModels\Glow1_red.mdl
Regeneration Scroll:
Abilities\Spells\Items\ScrollOfRegeneration\Scroll_Regen_Target.mdl
Scatter Shot:
Abilities\Weapons\Mortar\ScatterShotTarget.mdl
Spinning Burning Head:
Abilities\Spells\Other\ANsa\ANsaTarget.mdl
Spinning Feather:
SharedModels\Feather2.mdl
Hidden Missiles:
Alternate Meat Wagon:
Abilities\Weapons\MeatwagonMissile\T_MeatwagonMissile.mdl
Ballista:
Abilities\Weapons\BallistaMissile\BallistaMissile.mdl
Balls of Fire:
Abilities\Weapons\BallsOfFireMissile\BallsOfFireMissile.mdl
Bomb:
Abilities\Weapons\FlyingMachine\FlyingMachineMissile.mdl
Earth Brewmaster cool
Units\Creeps\EarthPandarenBrewmaster\EarthPandarenBrewmaster_Missile.mdl
Flaming Arrow:
Abilities\Weapons\FlamingArrow\FlamingArrowMissile.mdl
Oscillating Steam:
Abilities\Weapons\SteamMissile\SteamMissile.mdl
Storm Brewmaster cool
Units\Creeps\StormPandarenBrewmaster\StormPandarenBrewmaster_Missile.mdl
Treant Missile:
Abilities\Weapons\TreantMissile\TreantMissile.mdl
Hidden Units
Ancestral Guardian:
Units\Orc\AncestralGuardian\AncestralGuardian.mdl
Blood Elf Peasant:
Units\critters\Bloodelfpeasant\BloodElfpeasant.mdl
Fel Orc Berseker:
Units\Demon\ChaosOrcRange\ChaosOrcRange.mdl
Entangled Wisp:
SharedModels\EntangleWisp.mdl
Gragoyle Spire:
Buildings\Undead\GargoyleSpire\GargoyleSpire.mdl
Illidan Imprisioned:
SharedModels\IllidanImprisoned.mdl
Night Elf Fishing Boat:
Units\Nightelf\Nightelffishingboat\Nightelffishingboat.mdl
......
Sorry for huge post. People who have World Editor Unlimited can find these easly but just cliking on the missile/unit and go to Extra. there you see Hidden Effects Doodads etc.