In honor (or maybe inspite) of my move here I am offering to random commenters my 3 invites for Google Voice which like most of Google's services starts out as invitation only.
For those not familiar with it, Google voice gives you a single phone number that you can setup to ring any or all of your phones, saves and transcribes your voicemail online, gives you the ability to listen in on messages as they are being left, and as of just recently it now allows you to move your cell phone voicemail away from your carrier which gives you all the Google Voice functionality from your cell phone. Of course the real advantage is you just give out your Google Voice assigned phone number and no matter what happens in the future with your other numbers, you can be still reached using that same number.
I have been using the service since I got the invite back in July but because I rarely get calls outside of work I really haven't had the chance to put it through its paces so I am a bit short on details. But if you have more questions, you can find more of what it does here and here. And if you would like to try it, just comment on any post and close it with your desire for an invitation and later this week I will shoot out my invites to 3 of you.