Server mods

Server Mods are modifications to the official Minecraft server software. They generally fall into two broad categories: management and gameplay.

Management mods are commonly designed to make administration of servers easier by implementing tiered privileges for commands (such as kicking, banning etc). They are frequently implemented as "wrappers" which do not actually modify the main server .jar file, instead monitoring its output and sending commands to it.

Gameplay mods are modifications to actual game mechanics, such as restricting the placement of blocks commonly abused by Griefers (eg. lava, TNT), fixing bugs in the server (eg. making furnaces function before the update of 10th of September 2010) or adding new gameplay features.

Mod List
This is a list of wrappers and modifications.

Modification Specific Plugins
These plugins are not specifically made to modify Minecraft directory but instead are plugged into existing modifications.

Plugins for hey0's Server Plugin
These plugins hook into hey0's Server plugin. They are usually installed by placing the .jar inside  /plugins, and adding the plugins name to the plugins field in server.properties. Another more up to date list is here.

Bedrock Gap Insurance + Flat Earth v1.1 (Updated 10/30/10)
Simple plugin that automagically fills in any voids with bedrock. Never fall through the map again! Now also has an optional feature to convert the non-bottom bedrock layers into smooth stone. See thread for screenshot and more details!

ChannelChat
Adds channels within the chat system, similar to that seen in most MMO games. There is a global chat, local chat (only people within 20 blocks can 'hear' you), and a guild chat in which players can setup their own channels.

CraftIRC
Creates an interface between IRC and Minecraft chat, allowing users to communicate between the two chat services. Has configurable name colours, optional MC events to IRC ( [User has connected]) and plenty of other options.

CuboidPlugin
Allows protecting, removing, filling and replacing user selected areas (or cuboids) of the game world.

Daylight
Permanent daylight, implemented by checking the time every 60 seconds and resetting the time to daybreak as soon as sunset arrives.

GriefAlert
Helps admins try and pre-emptively prevent griefing by alerting admins to suspicious activity (very customizable) - such as when a player uses lava or removes water with a bucket.

GroupChat
Adds a /cg command that allows players to only send messages to those in their group (specified using groups.txt and users.txt).

HouseArrest
Stops players from moving a configurable distance away from the spawn point. It warns the player as they leave before teleporting them back if they choose not to turn back.

LocalChat
Splits chat into a local and global chat. In local, only players within 20 blocks can hear you. This mod was the inspiration (code was used from this plugin) ChannelChat.

Mapper
Plugin extending hey0's mod to add labels to Shade's mapper application from in game.

PoemBooks
Original example poem posted by hey0. Allows two way warping by using /setbook ' in two locations. You can then use /book at either location to warp between the two points (you must be within 4 blocks of the /setbook).

TimeRift
This plug-in lets you force your server to a specific time, and it will loop back to that time every 5 minutes.

TownyMod
Towny is a full plugin for Hay0's server mod that has a lord/mayor who controls the residents in his/her town, a town board (motd-like), and full population statistics targeting only active users. If all goes good, it should expand to countries and capitals cities. The towns will also work with the Mapper Mod to add labels.

Plugins for ZMA
These plugins are for Zicore's C# Admin.

IRC Integration
Creates an interface between IRC and Minecraft. Download - Forum