Glitter filaments are polymers mixed with glitter flakes to give a sparkly or glittery finish. The benefits here are certainly aesthetic not functional but that doesn't mean they are not useful! Glitter 3D printing filaments are a great way to add variation to the appearance of 3D printed products.
Always check the Technical Data Sheet of the glitter filament you are using as some may be abrasive and require the use of a hardened steel hot end. Glitter filaments will usually print using the same or similar settings to whatever carrier polymer has been used.