Cell Phones with Retractable Earpiece

I have a cell phone and I have an earpiece/headset that goes along with it. I keep the phone in my pocket, and my earpiece in my purse. I like to use the earpiece occasionally, for hands-free discussions, but it's not easy to find and attach the earpiece to the phone for unexpected incoming calls, especially if I'm busy.

So, here's what I'd like to see on the market: a cell phone that has a built-in earpiece/headset accessory, which retracts all the way into the phone, with no protruding plug or wire remaining when thoroughly retracted. This is important, as I have a nicely smooth phone with no protruding antenna or other stuff sticking out to catch or break.

The end of the accessory to enter the case of the phone would be the part that goes in the ear, with case materials built onto the outer side of the earpiece speaker. To open and use, a push-button release (or even a thumbnail divet) could be incorporated into the design. To retract, I would suggest another push of the button, like with certain vacuum cleaners or clothes irons.

The cell phone would operate normally when the earpiece accessory is fully retracted, but automatically switch to headset mode upon push-button release of the earpiece from the case, making it quick and easy to use for all calls. Plus, there's no fumbling or losing the accessory.