Earlier today a Death Knight in Juggernaut (US-Mal'ganis) assembled the world's first Shadowmourne. Shadowmourne is the Icecrown Citadel legendary axe, that is assembled through a long and somewhat difficult quest line. It is the most powerful two handed melee weapon currently in the game.

This item is the combination of a lot of dedication and skill on the part of Juggernaut, and a lot of luck in obtaining the 50 Shadowfrost Shards required to complete the final step of the quest. Congrats Modk!