Minecraft Junkie

The largest darkness-based mob spawner in the NewWorld is now hooked up the the StarGate system under the name "MegaSpawner" and is available for anyone to use. It has a level 30 enchanting table nearby, along with an iron block, an enderchest and - when I replace it - an anvil. As payment for this service, I keep the mob drops that fall into the collection area.

Features:

2 Beacons, giving a constant source of Regeneration, Resistance and Strength 2
2 Acrobatics grinders of different intensities
Non-PVP area so nobody can sneak up on you while killing
Cheap food and (fully repaired) bows available
Several shop items for "things to enchant" once you reach level 30