Memristor, a long postulated yet missing circuit element, has recently emerged as a promising device in non-volatile memory technologies. However, beyond its use as memory cell, it is challenging to integrate memristor in modern architectures for general purpose computation. In this paper we propose a non-conventional use of memristor and demonstrate its applicability to enhancing cache replacement policy. We design a memristor-based saturation counter which can track cache access history at low cost. Based on our counter design, we develop a cache replacement framework that is both reconfigurable and adaptive (MRAC). Our evaluation demonstrates MRAC's reconfigurability and adaptivity, which result in better performance and more robust performance improvement.