As a boy, I used to collect saga seeds (Adenanthera pavonina) on the top of a nearby hill. It was a fun and inexpensive activity to spend an afternoon among nature. If I was lucky or industrious enough; I could usually collect a small pile of these lovely seeds to add to my collection of other childish nick-nack at the end of the day.
Its Chinese name, "相思豆" (xiang si dou), would loosely translate to "longing beans". These vibrantly red, mildy heart-shape seeds can make a lovely gift to a loved one.