Best way to forward phone calls and textmessages?

I am looking for a way to forward phone calls and SMS/Textmessages. Yes, I know, there are services like www.voip.ms and they are great but mostly only for the US. Foreign numbers can be very expensive and often SMS forwarding is not possible.

Any ideas? Currently I am thinking of just having a couple of phones at home on with an android app that can forward calls and SMS.

Any other idea?