Automatically changes your Stack Exchange chat messages to Sᴍᴀʟʟᴄᴀᴘs

smallcaps.user.js

// ==UserScript==
// @name           Smallcaps.SE
// @author         Cameron Bernhardt (AstroCB)
// @description    Automatically changes your Stack Exchange chat messages to Sᴍᴀʟʟᴄᴀᴘs
// @version        1.1
// @namespace      http://github.com/AstroCB
// @include        *://chat.meta.stackexchange.com/rooms/*
// @include        *://chat.stackexchange.com/rooms/*
// @include        *://chat.stackoverflow.com/rooms/*
// ==/UserScript==

var smallCaps = {
  "a": "ᴀ",
  "b": "ʙ",
  "c": "ᴄ",
  "d": "ᴅ",
  "e": "ᴇ",
  "f": "ғ",
  "g": "ɢ",
  "h": "ʜ",
  "i": "ɪ",
  "j": "ᴊ",
  "k": "ᴋ",
  "l": "ʟ",
  "m": "ᴍ",
  "n": "ɴ",
  "o": "ᴏ",
  "p": "ᴘ",
  "q": "ǫ",
  "r": "ʀ",
  "s": "s",
  "t": "ᴛ",
  "u": "ᴜ",
  "v": "ᴠ",
  "w": "ᴡ",
  "x": "x",
  "y": "ʏ",
  "z": "ᴢ"
}

var field = document.getElementById("input");

field.addEventListener("keyup", function() {
  var text = field.value;
  text = text.replace(/([a-z])/g, function(match) {
    return smallCaps[match];
  });
  field.value = text;
});