Bukkit

Give unique powers to players

A bukkit plugin that allows the MOTD to be modified ingame.

Allow the mods/admins to contact you from ingame with out needing your email/phone number!

A simple way of finding out how your users got to your server.

MonsterIRC

MonsterParties allows your users to create parties in which their frends can join.

Fixes survival flight for ops.

Allow your players to explode when they die!

An awesome plugin that creates a moderator support system.

An API for developers allowing them to create areas of blocks.