*43# (Enable Call Waiting)
If you're someone who's always on the calls, then call waiting might be just what you're looking for. With call waiting, you can take a second incoming call by putting your first call on the hold. In fact, in some cases, you might also be able to switch between the calls. If you think you're on the phone to a scammer, for instance, and someone else calls you, you can switch to that call and take time away from the potential scammer to think things through and maybe ask for advice.