Windows 8 has an on-screen keyboard that you can use to type Emoji, even if you use a regular keyboard and mouse.
Today you can use Emoji pretty much anywhere, be it mobile or on the web with most modern browsers.
I have an iPhone 5s and every once in a while my wife and would be texting and I would send her a and she would be like 'why you sending me a square?' Then later she got a Nokia 1020 and then we could send each other Emoji's back and forth 😄 😃 😀 😊 ☺ 😉 😍.