UW-Madison researchers have demonstrated a highly consistent return point memory (RPM) in elastically recoverable monolithic vertically aligned carbon nanotube (VACNT) foams. This non-volatile memory arises from self-adjusting nanoscale frictional interactions, and this mechanism enables tunable dynamic modulus and loss factor controlled independently by strain amplitude and static precompression. Exploiting this dual tunability, the researchers have built a VACNT-enabled periodic waveguide whose group velocity slows with pulse amplitude yet accelerates under bias compression, enabling amplitude-selective wave focusing and filtering. The demonstration of consistent, friction-based RPM in an elastically recoverable soft material revives the concept of constitutive mechanical memory and opens pathways to lightweight materials that compute, filter, and modulate mechanical waves without electronics.