Because after you bought a Mac, you won't have any money left.
I second skype for communication. There's versions for Windows, Linux, Mac OS - I'm sure it works with Leotard, too.
It's free, and you can connect with everyone. Even with phones (well, that's not free, but dirt cheap. Especially if you want to reach someone abroad. We use it to speak with our business partners in Malaysia. Seems that their internet connection isn't that great, but we can reach their cellphones. And it doesn't cost several € per minute like it would if we would use a phone on our side).