Rigelian memory cotton was a type of material, a cotton-like fabric grown or manufactured in the Rigel system. It was used as a material for bed pillows.

Lieutenant Elizabeth Shelby used a pillow made from a stiff roll of Rigelian memory cotton in her quarters on the USS Yosemite in 2366 (NF - No Limits short story: "All That Glisters...").

By the name, a Rigelian memory cotton pillow seems likely to hold its shape when molded.