In the Netherlands, there is a book series called 'boekenweekgeschenkjes'. Every year a dutch author is invited to write a 90 page story. It is then published in small format, and distributed as a gift in bookshops during the 'boekenweek'.
These booklets are ideal for folding hearts. I like to create as many variations on my heart pattern as I can think of.
Interested in one of these hearts as a present for yourself or a loved one? I sell them for 10 euro a piece (shipping not included).