I read an article that I can't find at the moment which detailed a way to have Google Voice point to a SIP phone number which forwards to your phone in order to take advantage of the SIP service in order to

1. Have all calls use a data connection = no usage of cell-phone plan minutes.
2. Record each and every conversation.*

I really want to be able to accomplish this, primarily issue number 2, as all of the phone recorder tools in the Android Market essentially don't work for my Nexus One. I figure that I have one of two options with this. I could 1) use an existing (hopefully free) service which will do this for me or 2) I could set up a SIP service at my home. to somehow forward calls through my home server which will record the calls as well as forward calls to my cell phone.

Obviously, the path of least resistance is the one I'd like to go down. Can anyone help me out with this?

_{* I do understand that the legality of this varies from state to state here in the US.}