Flexible graphite sheets made by compacting exfoliated graphite (made from intercalated graphite) without a binder are high-temperature resistant and chemically resistant, as they are all graphite. Thus, they are suitable for harsh environments. Due to the cellular structure stemming from the exfoliated graphite and the preferred in-plane orientation of the carbon layers, the sheet is resilient under normal compression. The resiliency enables the application as a gasket (e.g., for replacing asbestos). The resiliency and piezoresistivity enable the application as a resistance-based compressive strain/stress sensor. The thermal conductivity enables applications as heat spreaders and thermal gap-filling materials. The electrical conductivity enables applications as heating elements, sliding electrical contacts and electrodes (including electrochemical electrodes). The ability to absorb and reflect electromagnetic (microwave) radiation enables applications in electromagnetic interference (EMI) shielding (including EMI gasketing) and electromagnetic pulse (EMP) protection. The electret (permanent electric dipole) behavior enables the application as a low-voltage power source.