I’ve used a variety of computer based VOIP over the years. My current preference in this space is Skype as it’s free for computer-to-computer calls and even allows calls to and from regular phones (at a fee).
Video and text chat are also provided, as is ‘white-boarding’ with additional plugins.
Skype is available for most platforms, even mobile phones… I’ve found that while the Windows beta versions has some additional features, the Linux release is rock-solid.
There are also several hardware based solutions, like Vonage, available to replace your traditional phone service… perhaps we’ll cover that later.
I found this a few weeks ago and it’s been quite useful in making sure that my username is common across most websites. In the past, I’ve only found one instance of other person that’s used my normal handle elsewhere on the internet, this tool will make that occurrence much less likely.
As indicated way back in my ‘Contact Information’ entry, I use several IM client networks. To make it easier on myself (and my poor computers), it’s usually easier to get an integrated client that connect to many services within one program.
For an even easier way to connect without software installations and to bypass many corporate proxy’s and/or firewalls is to use a web client.
My favorite (as I’m not aware of any others that are still online):
I’m listed as skotfred on MOST email and instant-messaging networks.