I use vonage at home and in our offices   I highly reccommend it. 
Here is my referral code if you want to sign up under me! 
http://www.vonage.com/?refer_id=tanker
I love my vonage I have had it for like 3 years now   
the best part is if you take the little router with you while travelling  you can use your vonage phone on any broadband connection and your phone will still ring to you even if you are in China at the time 
I have 3 numbers attached to it   one in Arizona, seattle, and Toronto 
it rocks!