New antenna material functionalities are required for reconfigurable antenna technologies. For these applications, RF circuit materials which are innately reconfigurable could provide increased functionality without added complexity. We have investigated two such materials: sulfuric acid-intercalated graphite, a tunable-impedance conductor; and a graphene oxide-metal nanoparticle composite, a semi-conductor with demonstrated negative differential resistance properties. This paper covers fabrication and characterization of devices using these materials, exploring their intrinsic tunability from DC to 40 GHz and their potential for application to reconfigurable RF technology.