This does exactly what says so. It's incredible simple to install and use.

The plugin also allow you to choose what languages will you support, which is great to avoid unecessary javascript imports.

I've missed a few features, like choosing the layout or support for legacy code. A few adjustments in my articles solved the problem, but other people with lot more content than me could have problems in this area.

Another suggestion would be integration with TinyMCE or JCE.