Can you use iMessage on your Macbook even if you don't have an iPhone?

I know that for iPhone users, you can connect your iMessage thing to your Macbook.
I don't have an iPhone but I have a lot of friends with iPhones.
I was wondering if there's any way I can group iMessage with them via my macbook.

Hi dear you can use iMessage in your newly installed Mac OS X Mountain Lion which supports thousands of features, it make easier to connect with people. The best part is that it's completely free and will work with everyone who have installed mac OS.

If you are signed in icloud when you installed your os, you are probably already signed in and you want to signed in manually then log in with your apple ID. Click on the blue & white chat bubble and start your conversation without the need of any iphone.

Take care.

Yep, you sure can. I do it all the time. The people who you text with iphones will not even know the difference - it will show up in their imessages/text messages!
http://www.gottabemobile.com/2013/01/24/how-to-set-up-imessage-on-mac/