Functionalized peptides can be used to form useful materials. The more hydrophobic dipeptides often form persistent micellar aggregates at low volume fractions in water. These subsequently can form gels on change of pH or addition of salts. There is a tension with this kind of material in terms of understanding and describing behavior with a significant focus on these materials as peptide-based. Many reports highlight (for example) the peptides packing into secondary structures like beta-sheets. A subset of peptide-based gelators have been described in terms of micellar behavior, but it is common to focus on low concentrations where gels are easily formed; phase diagrams are rare. The structures formed can often be persistent wormlike micelles and hence polyelectrolyte behavior is expected; there are significant similarities between ionic wormlike micelles and polyelectrolytes and analogies have been drawn in many cases. Indeed, wormlike micellar fluids are often referred to as "living polymers". Ultimately however to design useful materials, we need to understand and control molecular packing and translate properties across length scales. There are examples where useful materials have been made via hierarchical peptide assembly, but a key question is whether we can invert the approach; rather than observing a specific behavior and then using the outcome, can we instead determine what properties would be required for a specific material and then rationally design a self-assembling system to exhibit these?