Barrel (Factorization)

The Barrel is an item storage solution designed for storing a lot of a single item type. It can store 4096 (64 stacks of 64) of a single item. The front of the block shows the item it is holding, along with the amount of said item.

Usage
Right click on a barrel with an item in hand to put that item in the barrel. Double right click to put all of that item in your inventory into the barrel. Left click to remove an entire stack of that item. Sneak/Crouch left click to pull out a single of that item. The Barrel can be upgraded using an Extra-Dimensional Storage (Barrel Upgrade).

Applied Energistics
Barrels can be set up to be part of an ME Network from Applied Energistics, using a ME Storage Bus under the barrel and setting the item you want the barrel to store in the Bus' GUI. It is also recommended to configure priority properly, so the item set to be stored is actually stored in the barrel and not in other ME storage you may have on the network.

Buildcraft
Items can be inserted into the barrel using a Buildcraft Transport Pipe into the top side, and can be pumped out from the bottom side.