Carbon fibre rods.
Carbon fibre rods have a high strength to weight ratio and are suitable for a wide range of creative projects including prop construction, as a structural base for cosplay armour, pull/push rods in robotics, RC srengthening spars and for making sports equipment including kites.
When cutting, wrap masking tape around the place for cutting (this will minimise the chance of any splintering), mark the cutting line on the masking tape & cut with a fine tooth hacksaw / fine cutting disc (a junior hacksaw is also an option).