TooManyItems 1.7.2

Create and enchant items in-game, including mod items. Save and load entire inventories. Create unlimited stacks and tools. Switch game modes, test mods, create huge survival worlds, and more. Updated quickly!

Usage:

Turn On/Off: Press the “o” key while in the inventory screen. You can change this key by editing the configuration file.
Add items: Left-click on items in the right sidebar to add full stacks, or right-click to add one at a time.
Configuration file: Find the directory in which your minecraft saves folder and options.txt are, and once you have used TMI at least once you will also find TooManyItems.txt there. This contains options that you can change, not all of which are documented yet.

Download: http://www.5minecraft.net/toomanyitems/