Newegg has Polycom OBi200 1-Port VoIP (Voice Over IP) Digital Internet Telephone Adapter w/ Google Voice, SIP & Fax Support for $49.99 - $10 w/ promo code 63WTNTY259 = $39.99. Shipping is free.
Using this device along with your existing broadband Internet connection, you can make and receive phone calls using a multitude of VoIP services for free or at a fraction of the cost a traditional telco would charge.
Use Google Voice with the OBi and enjoy free calls inside the USA and Canada.
Call internationally at amazingly low rates to over 150 destinations.
When someone calls, ring multiple OBi devices, anywhere.