For those of you into Minecraft, you are able to play a pre-release version up the upcoming 1.8 released–called the “Adventure Update.” Developer Jens Bergensten was kind enough to link everyone to the necessary files via his Twitter page. Simply put, grab the necessary .jar file and use it to replace the current one in your .minecraft folder.
Most Windows users can hit the start button, and type %appdata%/.minecraft/bin in the search bar, the the folder should pop up.
If that doesn’t work, you can get to it the long way at:
C:\Users\*username*\AppData\Roaming\.minecraft — Replacing *username* with your own username. Just keep in mind you may have to show yourself hidden files first.
You can grab the updated Minecraft 1.8 Beta Prelease .jar file here.
You can get the updated server .jar file here.