Chat Mods

BasicChatMods

BasicChatMods aims to be a simple chat addon promoting users to customize it with lots of documentation. each module is split into its own file with small comments and guides.
Curse, WoWInterface

Chatter

Lightweight chat improvements. Features: Hiding buttons, Linking items, enchants, spells, and quests in custom channels, Custom aliases for channel names, Coloring of player names by class, Custom font and font size for your chat frames, Custom background, border, and positioning for the edit box, Scrolling your chat frames with the mouse wheel, Sticky channels, configurable, Ability to copy a chat frame's contents to your clipboard, Ability to copy URLs to your clipboard, Ability to customize the background and border of your chat frames, Timestamps, A /tt command to send a tell to your target, A module that turns the word "invite" into clickable links that let you invite the speaker, Highlights, Chat fading toggles, Text justification, Autologging (Off by default)
Curse

PhanxChat

PhanxChat is a simple, functional chat mod. Features: Hides the chat scroll buttons, Hides the chat menu button, Shows the scroll-to-bottom button only when you're scrolled up, Enables mousewheels scrolling in the chat frames, Moves the chat edit box to the top of the chat frame, Enables arrow keys in the chat edit box, Disables the flashing effect on chat tabs, Locks chat tabs to prevent accidental undocking (hold SHIFT to drag), Configures chat text fading, Sets the fade-in alpha for chat frames, Removes the brackets around player names, Colors player names by class, if known, Remembers channel colors by name, not number, Shortens channel names and chat strings, Enables sticky chat for all chat types, Suppresses channel leave/join notifications, Suppresses repeated messages in public channels, Makes URLs in chat clickable for easy copying, Colors URLs in chat and adds brackets around them, Adds "tell target" functionality, Auto-enables chat logging.
Config: /pchat
WoWInterface, Curse

Prat3

Chat mod that lets you change many chat options. Options can be toggled on/off. Toggle the chat menu and chat window buttons on and off, Shortens channel names in the chatframe, Allows channel coloring by channel name, Enables item linking in all channels, Adds keybindings for different chat channels, Color player names by class, set brackets around player names, Enables mousewheel scrolling for chat windows, Makes chat channels sticky, Adds a slash command (/tt) and keybinding to send a message to your target, Adds timestamps to chat windows.
Config: /prat
Curse

rChat

A simple chatmod. Features: editbox to the top, URL copy, ALT-invite for players, SHIFT-mousewheel scrolling for scrolling chat up and down at once, chatframe colorfading disabled (color stays at the one you selected for the chat), alpha for not selected chat tabs can be changed from 0-1, chat tab graphics can be switched on/off, makes chatframe movable anywhere (edges of screen), adds outline to chatfont, removes buttons, channel name replacements, removes black bar on combat log.
WoWInterface

Instant Messengers

Cellular

An instant messenger mod that pops up a window when you receive a whisper. Opens a new window for each conversation. Allows you to close a window and return to the conversation later.
Config: /cellular
WoWInterface, Curse

WIM (WoW Instant Messenger)

WIM (WoW Instant Messenger) helps you to manage your whispers by making them into a classic instant messenger interface such as AIM, Yahoo and MSN. With game play in mind, WIM has a large array of options where you can customize how WIM interacts during different situations, such as while you are in combat or in town talking to friends or selling your crafts.
Curse
WIM Skin Suite, WIM Skin Suite: CityScape

Spam Filters

BadBoy

BadBoy will actively scan your chat for possible spam, when found it will block all spam that is found from appearing and report the spamming player automatically.
WoWInterface, Curse
BadBoy Levels: Filter Whispers By Level, BadBoy CCleaner: Filter Crap From Chat
Review: WoW Insider

devnull

Makes your life in WoW more pleasant by ignoring various chat annoyances while in a capital city. It will ignore people who /yell, spammy NPCs (ie. Ironforge bread vendor, Topper McNab in Stormwind etc), duel spam (A has defeated B in a duel), emotes, drunk spam (X looks tipsy), tradeskill spam.
Config: /devnull
Curse

NoGuild

Messages that look like guild recruitment spam are blocked from General, Trade, and whispers. There are no notifications to you or the sender, no dependencies on other addons, and no options to fiddle with. It just works. It will automatically disable itself while you are unguilded and have disabled the "Decline guild invitations" option in the default UI, since presumably this means you are interested in guild invitations.
WoWInterface, Curse

Miscellaneous Chat Mods

ChatKeys

Allows you to bind keys to open chat channels. Also gives a binding for tell target.
Config: Key Bindings
Curse, WoWInterface

ChatLinkIcons

Adds icons to links in chat.
WoWInterface

ChatSounds

Plays sounds based on events in chat.
WoWInterface

LaLaLa

Blocks chat and emotes from hostile players.
Curse

LinkWrangler

LinkWrangler will allow you to open multiple item link windows from text links in the chat window. Ever been asked to compare items from the chat window for someone? Sitting there clicking back and forth between the two links, trying to remember the statistics of each? Ever want to look at multiple items as they blaze by you in the chat frame only to find out that the other links have long since disappeared by the time you are done with the first? This is the addon for you!
Curse, WoWInterface

Misspelled

Watches chat messages you type, highlighting misspellings. Misspelled words may be right clicked to obtain a list of replacement suggestions.
Curse

NeonChat

Colors the chat input and chat border to match the chat you are about to write.
WoWInterface