My good friend David created a chatbox for the website XboxMb but he did not create a desktop application for it, so I went ahead and created one for him. Download here

Features:

Lists what everyone is saying in the xboxMB chat
Account rank support
Account privileges support (Mod/Admin displayed)
AFK support (Shown with *)
You can type messages to the chat so long as you're logged in
@'ing support
User list
Can double click someone's name in the userlist to start a private tab with them
Chat history support
Private message alert support
Server side settings interaction support