What is this?

This is a plugin that allows players to break obsidian, ender chests, enchanting tables or any other customisable block with TNT, creepers among other exploding things, after a set amount of explosions. Really useful for especially faction servers.
It will also show cracks on the block depending on the remaining health of the block.

How to use it?

Simply drop the plugin in your plugin folder and you're ready to go. There are however a lot of stuff you can configure in the config.yml file, including which blocks are affected, the strength of the blocks and the explosion radius.
After that, just try to blow some obsidian up. You'll need multiple blocks of TNT (of course). You can also right click the block with a stick to check the remaining health or simply see how cracked up the block is.

More in-depth instructions regarding the configuration options are located at the BukkitDev page.