Texture Mod: Use a Transparent Texture Pack to Find Hidden Treasures (All Versions)
This texture hack makes the Minecraft ground transparent so that you can see through them. This makes it easier find dungeons, cave systems, minerals, or even hidden chests. This even works online on SMP servers. This cheat works with all version of Minecraft. To use this cheat download here.
Then follow this tutorial:
Open up Minecraft and login
Click on “Mods and Textures Packs”
Select “Open Texture Pack Folder”
Move the X-Ray.zip folder into your Texture Pack folder
Select X-Ray.zip in Minecraft and click Done