What does this plugin do?
LimitedPistons is a very lightweight plugin that can be used to block certain block types from being moved by pistons. This can be used to prevent griefers using slime blocks or stop custom blocks added by other plugins from being moved. (We use this plugin as a fix for a plot system to stop players from moving blocks outside their plots.)
Config
blockedMaterials: - 1 - GRASS
The config supports both block id's as well as bukkit's material names.
Anything else?
Nope. The plugin is super light-weight and really only has that one function. I hope it's useful for someone!