I'm also sometimes tempted to remove old and mostly unused plugins
(see bug #668778)
But once they are in trunk, some users might depends on them.

So I think we should create a new munin-plugins-* package for them.
This bug report is here for reminding.
For naming, "munin-plugins-osoblete" or "munin-plugins-old" comes to my mind.

Would it also be possible to have some usage stats reported ?
Something a-la popcon, but for plugins...