This is an easy, fun way to play with your food! If you have picky kids, you could do some juicing of fruits and veggies and then create these "caviar" jellies out of it. This is a great molecular gastronomy project!
Until relatively recently, spherification ingredients and tools were hard to come by unless you were a professional chef. With the growth in popularity of molecular cooking, a wide variety of spherification tools and ingredients are now available online.