OK, so I was talking on my cell phone with my girldfriend, and the phone I got her has the free cingular to cingular minutes. I originally called her (or she called me, whichever) with my cingular phone and was talking for about 10 minutes. I called her on my house phone while our cell phones were still connected, because my cingular phone didn't have free cingular to cingular. So she answered the beep and I hung up my cingular phone and talked on my house phone. We talked about 20 more minutes on top of that. Did this twice. This was in the afternoon, long before my night/weekend minutes started. I went online to look at the minutes used on her phone, and it only deducted from the mobile to mobile minutes and left my daytime minutes alone. Give it a try and let me know if it works for you too. Just call cingular to cingular, then call with another line