There's only one plugin here so far:

== Multimemory ==

This graphs the memory usage of several different processes on a single graph. As of Munin 1.4.2, this plugin is included in the default, bundled plugins - so if you're using a recent version of Munin, you'll probably already have it. It's called multips_memory there, to better reflect its origin.

If you have a useful change to this plugin you should look at changing the official version:
 http://munin.projects.linpro.no/browser/trunk/plugins/node.d/multips_memory.in