My wife bought me this for Xmas, and it's probably one of the best ideas ever. The Vtech DS6322 w/ Bluetooth, is a 3 or 4 phone kit with bases (with an answering machine) that has Bluetooth capability. Buy.com has it here. So, after I paired my wife and I's cell phones to the base, now, when we come home our cell phones connect to the base, and then calls that come in our cell phones can be answered via the regular phone.
The regular phone has all the regular cordless phone buttons that you'd expect to see, plus one additional, a "Cell" button. Whenever a phone call comes in on the cell phone, we just tap this button and we can answer it, all without having to run all over the house to try and find our cell phones. It's convenient, as we have the base station (w/ Answering Machine) and our cell phones plugged into this piece of handiness from Pottery Barn (ours is black). The cell phones stay put in that area, along with the base station, and now we don't have to sprint all over the house looking for phones when one rings.
You can even import the phone books of the phones into the base station. (Nice!) You can set a static ringer, per phone line, so you know exactly which line someone is calling in on.
I recommend it.