You have something important to say but player(s) don't listen you?
Using this plugin you can "poke" specific player with:
When you type /poke [nickname] [message] command (for example. /poke player123 any message) The specific player get message:

And you get:

The Configuration file is really simply and let you enable or dissable any effect
sound: true - Enable/Disable Thunder Sound
confusion: true - Enable/Disable Confussion Effect
slowdown: true - Enable/Disable Slowdown Effect
darkness: true - Enable/Disable Darkness Effect
fillchat: true - Fill chat area with messages, or send only one
text1: You are poken by - Translation line
text2: With message - Translation line
text3: Succesfull poked - Translation line
You can disable or enable any function by config.yml (And you can easily translate plugin in configuration file).