Google Talk. Can I make voice calls without a landline?
To make voice calls with the Google Talk client, all you need is access to a microphone and speakers (we recommend using a headset for optimal voice quality). If you don’t have a landline telephone at your desk, you can call computer-to-computer with Google Talk. If you’re having difficulty sharing ideas via email or chat, simply call your co-worker to get clarification. Tip: You can make voice calls in your email account as long as you log in to the Google Talk Client on your desktop.