This paper presents a novel and complementary mechanism, called Link-Indexed Statistical traffic Predictor (LISP) to improve IEEE 802.11 Power Saving Mechanism (PSM). LISP employs a simple, light-weight traffic prediction mechanism and enables each node to seek the inherent correlation between ATIM ACKs and incoming traffic. Thereby nodes en route can stay awake in the BI in which a packet is anticipated to arrive, thus bridging a "freeway" for the packet to rapidly traverse the route. Meanwhile, the number of duty cycles is minimized and more energy is conserved. We conduct analytical and simulation studies and demonstrate the effectiveness of LISP.