Rugged Leather

Rugged Leather is used mainly by Leatherworkers to create various leather armor.

Source
Rugged Leather is the last stage of non-Outland leather skinned directly from normal monsters(lvl 55-60). Leatherworkers with 250 skill can create a Rugged Leather from six Thick Leathers.

A good location to get rugged leather is in Un'Goro Crater at Fungal Rock killing the gorillas there. Perhaps a better location is Winterspring killing the bears and chimaera in the north and the yetis (there are loads with good respawn in and outside the cave just east of town)

As an Ingredient
Rugged Leather is used in the following recipes:

Blacksmithing

 * Corruption (Sword)
 * Dawn's Edge
 * Enchanted Battlehammer
 * Huge Thorium Battleaxe
 * Imperial Plate Belt
 * Imperial Plate Shoulders
 * Ornate Thorium Handaxe
 * Thorium Boots
 * Volcanic Hammer

Enchanting

 * Enchanted Leather

Engineering

 * Dark Iron Rifle
 * Field Repair Bot 74A
 * Large Blue Rocket Cluster
 * Large Green Rocket Cluster
 * Large Red Rocket Cluster
 * Lifelike Mechanical Toad
 * Masterwork Target Dummy
 * Powerful Seaforium Charge

Leatherworking

 * Black Dragonscale Breastplate
 * Black Dragonscale Leggings
 * Black Dragonscale Shoulders
 * Blue Dragonscale Breastplate
 * Blue Dragonscale Leggings
 * Blue Dragonscale Shoulders
 * Chimeric Boots
 * Chimeric Gloves
 * Chimeric Leggings
 * Chimeric Vest
 * Chromatic Cloak
 * Dawn Treaders
 * Devilsaur Gauntlets
 * Devilsaur Leggings
 * Frostsaber Boots
 * Frostsaber Gloves
 * Frostsaber Leggings
 * Frostsaber Tunic
 * Girdle of Insight
 * Green Dragonscale Breastplate
 * Green Dragonscale Gauntlets
 * Green Dragonscale Leggings
 * Heavy Scorpid Belt
 * Heavy Scorpid Bracers
 * Heavy Scorpid Gauntlet
 * Heavy Scorpid Helm
 * Heavy Scorpid Leggings
 * Heavy Scorpid Shoulders
 * Heavy Scorpid Vest
 * Hide of the Wild
 * Ironfeather Breastplate
 * Ironfeather Shoulders
 * Living Breastplate
 * Living Leggings
 * Living Shoulders
 * Might of the Timbermaw
 * Mongoose Boots
 * Red Dragonscale Breastplate
 * Rugged Armor Kit
 * Runic Leather Armor
 * Runic Leather Belt
 * Runic Leather Bracers
 * Runic Leather Gauntlets
 * Runic Leather Headband
 * Runic Leather Pants
 * Runic Leather Shoulders
 * Shifting Cloak
 * Stormshroud Armor
 * Stormshroud Pants
 * Stormshroud Shoulders
 * Swift Flight Bracers
 * Volcanic Breastplate
 * Volcanic Leggings
 * Volcanic Shoulders
 * Warbear Harness
 * Warbear Woolies
 * Wicked Leather Armor
 * Wicked Leather Belt
 * Wicked Leather Bracers
 * Wicked Leather Gauntlets
 * Wicked Leather Headband
 * Wicked Leather Pants

Tailoring

 * Felcloth Boots
 * Felcloth Shoulders
 * Runecloth Bag
 * Runecloth Boots
 * Runecloth Gloves
 * Runecloth Shoulders
 * Soul Pouch