This pillow is stuffed with human hair.
On Mars everything would be a resource – even down to bodily waste. Hair could provide a useful alternative to use for all kinds of things around the house from soft furnishings, to potentially even as a thread for sewing. It is also completely biodegradable rather than taking synthetic padding with you to stuff pillows or mattresses with.
Here on Earth we collected leftover hair from hairdressers to use. On Mars perhaps you would carefully save your hair as you naturally shed some everyday, until you had enough for your purpose.
We also have experimented with making paintbrushes with human hair bristles.