We're never to old for userscripts right?
// ==UserScript==
// @name Clear Chat Button
// @namespace http://your.homepage/
// @version 1.0
// @description Nukes everything in chat
// @author UniKitty
// @match http://chat.stackexchange.com/rooms/*
// @match http://chat.meta.stackexchange.com/rooms/*
// @match http://chat.stackoverflow.com/rooms/*
// @grant none
// ==/UserScript==
function go() {
var clearButton = document.createElement('button');
clearButton.setAttribute("class", "button");
clearButton.setAttribute("id", "clear-chat");
clearButton.innerHTML = "Clear Chat";
clearButton.addEventListener("click", function() {
if (confirm('Are you sure you want to clear the messages?')) {
document.getElementById('chat').style.display = "none";
}
});
var showButton = document.createElement('button');
showButton.setAttribute("class", "button");
showButton.setAttribute("id", "show-chat");
showButton.innerHTML = "Refresh Chat";
showButton.addEventListener("click", function() {
document.getElementById('chat').style.display = "";
});
var chatButtonContainer = document.getElementById('chat-buttons');
chatButtonContainer.appendChild(clearButton);
chatButtonContainer.appendChild(showButton);
}
go();
This adds in a button to chat:

When you click it, there's a poopup asking for confirmation.
And boom! Everything is gone!
To install it, just copy the text into a file and save it as something.user.js
. Then install something like greasemonkey and drag the file into firefox (or chrome). Then install the userscript!
Sound effects not included