The Slacker's Guide to World of Warcraft

Gatherer
http://gathereraddon.com/

If there's one thing we hate, it's trudging all over the wide expanse of Azeroth on a hunt for enough of some damn herb we need for our latest potion. With Gatherer, this lament is a thing of the past. Gatherer records the position of mineral veins, herbs and treasure chests (and anything else you can collect) on both your mini-map and world map for easy reference when looking for a particular material. You'll never again have to deal with spotting a blip on your mini-map and fighting through the waves of monsters that stand between it and you only to find that some cheeser Paladin is already there, harvesting what is rightfully yours... or maybe you still will be confronted by this nauseating situation, but at least you have a mapful of other locations available for gathering that exact same resource. The schlep across the lands of Azeroth is tough enough without having to remember where to get iron, Gatherer will solve this woe for you permanently.