Emooji

Emooji is a lightweight and easy to use software utility that enables you to quickly add fun-looking emoticons in all the comments you post on Facebook, in just a few clicks, so you can impress everyone with your smileys.
The application comes in a single EXE file, but functions as a browser extension. As such, after you run the installer, you will be able to use Emooji both in Google Chrome (you need to enable it first) and in Firefox.
Subsequently, every time you access your Facebook account and wish to make a comment on a picture posted by someone or even on a person's status, you will be able to click on the smiley face from the 'Write A Comment' field and display a small window, featuring countless emoticons.
Emooji organizes the available emoticons in three different categories, namely 'Regular' (which are generally available on Facebook), 'Secret', and 'ASCII', rendering a wide array of emotions, ranging from happy, to heartbroken. You can add various types of hearts, presents, a Christmas tree or a snowman, flowers, balloons, hand signs and others.
At the same time, in the 'Secret' section of Emooji, you can also find several animals (snake, mouse, wolf, cat, pig, monkey, horse, elephant, fish, dolphin, octopus, cow, penguin, dog, and many others). The 'ASCII' group of emoticons features various 'old-style' smileys, which you can use to render emotions in a less colorful yet just as inventive manner.
To summarize, Emooji is a simple and efficient program which installs in your web browser, be that Google Chrome or Firefox, allowing you to access it when writing comments on Facebook and add various popular or less known emoticons to the reply.