Tutorials/Playing and saving Minecraft on a thumb drive

This tutorial explains how to run Minecraft on a Thumb/Flash/USB drive. It is useful if you want to keep your game data (worlds, texture packs, server list...) when switching computers.

What you will need

 * A Flash/Thumb drive with at least 256MB of space.
 * A computer that runs Windows.

Preparations
As minecraft requires more than the single one file it obviously installed, we will collect all the files needed to run and sort them onto the thumb drive for easy access.


 * Plug in your thumb drive and open it
 * Create a folder, name it Minecraft portable (or whatever you want) and double click it
 * In that folder, create two new folders and name them bin and data
 * Note: they must have those EXACT names since we're going to use them in the following steps.
 * There are now three folders on the thumb drive, bin and data, both within Minecraft portable.

The client
Now to get and copy the client/launcher to the thumb drive:


 * Locate your minecraft client
 * should be something like C:\Program Files\Minecraft\Minecraft.exe
 * If you have a shortcut on your desktop/start menu, you can right click it, click "Properties" and click "Open File Location".
 * Copy said .exe and paste it into the bin folder

The data files
The Minecraft data files are still missing, here's how to find them:


 * Press +
 * type %APPDATA%
 * hit ENTER
 * Locate your .minecraft folder and copy it
 * Copy said folder and paste it into the data folder
 * Note: any texture packs or other stuff you might have are usually already included here.

Setting up
Now that all the data files are there, we need to tell windows how to handle them on the thumb drive and for that, we will create a batch file.


 * Press +
 * type notepad
 * hit ENTER
 * Here is the code, copy and paste it into notepad:

SET APPDATA=%CD%\data bin\minecraft.exe


 * Now click File, Save as ...
 * Locate your Minecraft portable folder (not bin or data)
 * As Filename use "Launcher.bat"
 * Note: yes, including the "" - else you will get Launcher.bat.txt and it will not work.

All done
That's it, all should work perfectly. Every time just before minecraft launches there may appear a window for a short time but that's expected, it's just the batch file working. A simple double click on the newly created Launcher.bat will start minecraft and you can play as usual.

Keep in mind however, should you ever want to use a theme pack or other addon/plugin: when the respective instructions tell you to copy files you will need to use the .minecraft folder on your thumb drive. However, said themes/addons will then of course be integrated in your portable version.

Source
If you have any trouble or just don't understand, the original source can be found in this thread.