Have you ever looked at a sick lookin npc and said "Man I wish I had his armorz"? Well then that dream is now reality.
Step 1: Open WoW Model Viewer (easy?)
Step 2: Choose your model (human, belf, nelf, dwarf, etc)
Step 3: Click the Character tab in the upper right and then choose Load Npc Outfit.
Step 4: Now you can search through all the NPCs or you can be smart and have one predetermined. For this I will choose Cultist Corruptor.
Most of these items say something like "NPC15809" or something like that. The number after that in brackets is the displayid. If it is an actual in-game item, then the second pair of brackets is the displayid. For example "Abjurer's Gloves [14570] [14895] <- displayid.
Here are some more people and examples:
Highlord Tirion Fordring
http://img256.imageshack.us/img256/2...ingmmowned.jpg
Argent Crusader
http://img824.imageshack.us/img824/3...dermmowned.jpg
Instructor Razuvious
http://img833.imageshack.us/img833/5...rrazuvious.jpg
Bronjahm (Forge of Souls)
http://img375.imageshack.us/img375/9...ahmmmowned.jpg
Now some NPCs are unique so you can't have their armor (Silvermoon Guardian, Baron Rivendare, Lich King ). Have fun with this. Hope it opens up a lot of doors for you guys.