I've been using jmp.chat recently for this (SMS sent over XMPP and phone calls via SIP). I actually liked it so much I ported my old number and got a data only

I've been using jmp.chat recently for this (SMS sent over XMPP and phone calls via SIP). I actually liked it so much I ported my old number and got a data only plan, now I can launch Dino or something and get SMS on my desktop. I really wish one of the big carriers would embrace something like this.