they are simply the most tender part of the chicken breast. you can use them wherever you would use a breast. just enter chicken breast into the search box at spark recipes and a lot of recipes will pop up.
if you poach them or lightly saute them, you can toss them into a salad, make chicken salad, or slice thinly for sandwiches. you can pound them flat and use in any recipe that calls for veal scallopini. you can chunk then and use in stir fry.