This paper reviews a number of low-swing on-chip interconnect schemes, and presents a thorough analysis of their effectiveness and limitations. In addition, several new interface circuits, presenting even more energy savings, are proposed. Some of these circuits not only reduce the interconnect swing, but also use very-low supply voltages, so as to obtain quadratic energy savings, The performance of each of the presented circuits is thoroughly examined using simulation on a benchmark interconnect circuit. Energy savings with a factor of seven have been observed for some of the schemes.