If you make and receive phone calls on a regular basis, then you may have something to gain by installing a new free jailbreak tweak called LetMeKnow by iOS developer Kiran Patil.
LetMeKnow provides iPhone users with an ounce of haptic feedback whenever a phone call connects or disconnects. It works regardless of which party disconnects the call, and it can prevent you from having to plaster your phone to your face until someone picks up your outgoing calls.