Some products emblazoned with the "Use Libraries and Learn Stuff" motif. This is one of the many derivatives of the World War Two "Keep Calm and Carry On" poster.
The poster in particular now adorns the walls of libraries in several countries, and has been used in several pro-library demonstrations, protests and marches.
I keep prices low as this isn't an earning thing. I get around a dollar or pound or buck per item; Zazzle get the rest. My take ends up going to charities (UK and US) which support research into Progressive Supranuclear Palsy.