Switch Ooma for something cheaper?

We still have a home phone, mainly because we sentimentally like our old phone number we have had for years. Almost everyone uses our cell phones (with the exception of the rare doctor's office call). Recently our Ooma bill doubled to $8 a month (a tax issue in our state, I think). I'd like to get something free/cheaper to port our number to with minimal minutes, considering we rarely use it--but we don't want to give up the number all together. Any suggestions? I was thinking Freedom Pop.