not high-tech, and not _especially_light, but highly malleable … copper
depending upon length and cross-section dimension of course;
i.e. you will probably be able to bend a .062" dia. x 1.0" piece of round stock with your fingers. A .125" dia. x 1.0" piece of round stock; probably going to need to use pliers.
some dimensional information would help out the decision making process a great deal.