TooManyItems

TooManyItems is a mod created by Marglyph. The mod allows the player to visually choose and get directly in his inventory any object (blocks or items) from the game without the need to type any command like "/give " (unlike INVedit, which requires going to the menu to edit your inventory), including acquiring infinite stacks of items, blocks and infinite tools. As well as this, it also allows you to save up to seven different inventories and even throw stacks into the trash when they are not needed. The mod is currently compatible with Beta 1.2 through 1.2.3. The mod needs Mods/Modloader to make unlimited stacks of blocks refresh automatically. Most recently, buttons at the top left corner of the inventory screen have been added. The buttons can switch your game mode from survival to creative and back, change time of day, turn rain and snow on and off and delete your entire inventory.

Use
TooManyItems does not need ModLoader to run, nor any other mod, but ModLoader is needed for unlimited items. When you are playing, there is a menu that displays all the blocks, including ones normally not obtainable in creative such as End portal blocks. Clicking an item in the right will instantly place 64 of it in your inventory, whereas holding shift and clicking will place an infinite stack of 111 in your inventory, and right clicking will place one block in your inventory. In 1.0.0 now you can change from creative mode to survival mode. You can also change from day, midday, afternoon and midnight, with the toolbar at the top. If you do not like this feature then you can go to the config file and set itemsonly:false to true.

Trivia

 * In SSP, if you shift click on armor items, as an attempt to get infinite armor, and then equip it you will receive absolutely no damage from anything (with the exception of the void) even after the armor if removed or thrown away in the trash.
 * You can hide the TooManyItems box and information by pressing 'O'.
 * While not wearing armor if you are flying and you change to survival mode, press shift and when you hit the ground you will take damage depending on how high up you are
 * Known to update to Minecraft's current version very fast.
 * On Vanilla servers, TooManyItems will drop items in front of you, instead of placing stacks of 64 directly in your inventory.

Download
The file can be downloaded from the forums here and has compatible versions for Beta 1.2 through 1.2.3.

TooManyItems