Common yarrow is an all-around good plant. 
It makes a good cover crop.  You can throw it in with your lawn and keep it mowed with your grass.  It is very soft and nice for bare feet.
In the garden, it will grow to about 3 feet tall.  Yarrow can spread aggressively, so plant it with other aggressive plants.
It has medicinal properties- heals wounds, relieves anxiety.  A spit poulitice can remove the venom from a sting. (Always do your own research on medicinal herbs.)