For the plate wearers, here is an absolutely ridicolously colourful set if you want to look like a mixture of a rainbow and a clown:
For the head, I like two choices: Crown of Empowered Fate (Crown of Empowered Fate - Item - World of Warcraft) - Drops from Reliquary of Souls in Black Temple, or the Crimson Beholder Eye (Crimson Beholder Eye - Item - World of Warcraft) - Drops from Collidus the Warp-Watcher (Collidus the Warp-Watcher - NPC - World of Warcraft) - Rare Mob in Shadowmoon Valley.
The shoulders are kind of a hard part because most of them will totally overshadow the rest of the gear. Finding a good piece for this has been the hardest part for me, but if you aren't a pally (if you are, i'd recommend the Tier 2 shoulders as the Set is missing yellow) I would either take the Glorious Shoulder Pads (Glorious Shoulder Pads - Item - World of Warcraft) - Random Drop, get it from the Auction House, or Fanblade Pauldrons (Fanblade Pauldrons - Item - World of Warcraft) - Drops from Shirrak the Death Watcher in Auchindoun.
For the chest, Breastplate of Annihilation (Breastplate of Annihilation - Item - World of Warcraft) - Drops from The Prophet Skeram in AQ40. As purple as it gets.
For the cloak, Shadowmoon Destroyer's Drape (Shadowmoon Destroyer's Drape - Item - World of Warcraft) - Drops from Teron Gorefiend in Black Temple.
For the waist, Rainbow Girdle (Rainbow Girdle - Item - World of Warcraft) - Drops from Hearthsinger Forresten in Stratholme. This one is just great.
For the bracers, it doesn't really matter as they aren't visible anyways.
For the gloves, Gauntlets of Martial Perfection (Gauntlets of Martial Perfection - Item - World of Warcraft) - Drops from Gruul in Gruul's Lair. I'm not really happy with those but the green is pretty cool imo.
For the legs, Legplates of the Destroyer (Legplates of the Destroyer - Item - World of Warcraft) - Drops from Moam in AQ 20.
For the feet, I can't really say a lot about those because they all look different on a Tauren than on the other races. I like the Fel Iron Plate Boots (Fel Iron Plate Boots - Item - World of Warcraft) because they're dirt cheap and pretty colourful.
There are a lot of weapon lists floating around on the internet so I won't say too much about those, but here are just a few that get overlooked too often in my opinion:
Twohanded Axes: Crow Wing Reaper (Crow Wing Reaper - Item - World of Warcraft) - Drops from Talon King Ikiss in Sethekk Halls (Chance on the Anzu mount if you farm this) and Lucky Strike Axe (Lucky Strike Axe - Item - World of Warcraft) - Random Drop, get it from the Auction House. Looks absolutely ridiculous and has extremely outdated (read:bad) textures.
Twohanded Maces: World Breaker (World Breaker - Item - World of Warcraft) - Drops from Fathom-Lord Karathress in Serpentshrine Cavern, The Oathkeeper (The Oathkeeper - Item - World of Warcraft) - Random Drop, get it from the Auction House, The Hammer of Destiny (The Hammer of Destiny - Item - World of Warcraft) - Random Drop, get it from the Auction House, or Hammer of the Naaru (Hammer of the Naaru - Item - World of Warcraft) - Drops from High King Maulgar in Gruul's Lair.
The complete "set" will look like this: imgur: the simple image sharer imgur: the simple image sharer
Please don't hate on the style, I know that not everybody likes it this colourful, but I'm sure that a few of you will do.
Sorry for possible mistakes I've made (checked everything).