Funniest drops : Tear stained handkerchief
from AV alliance NPCs and Vial of Tears
from slimes in Nethercite mines. Although the Steamy romance novel
pickpocketed from any blood elf NPC in game (including raid bosses ?!?) and a quest item Booterang
are among the overall best
PS: Read the comments on the items
Edit: Just remebered one of most useless items, Shriveled heart
that drops in troll infested Zul'Farrak, can't be sold or disenchanted and is a neck item.....