Popcorn forks, zoo sticks, and orange peelers
The Popcorn Fork wants to be the fourth utensil in your place setting. Cute, but what's the matter with fingers? And I don't get the concept of Fun Du at all -- you're supposed to dip your popcorn in cups of gooey stuff, eat it from the Popcorn Fork and then put it back in the common bowl? Eww! (Via Reenhead.)
Zoo Sticks, on the other hand, are a much more practical innovation: kid-friendly chopsticks that will put that plate of veggie lo mein in your child's belly rather than on the floor. I wish they'd catch on in Chinese and Vietnamese restaurants; meanwhile we carry our own. (See also Fish Sticks and Rookie Chopsticks.)
However, if I were outfitting a kitchen on a desert island, the one cheap plastic utensil I couldn't do without is an orange peeler. I don't know why this thing isn't universal: it changes a sticky, frustrating procedure into a simple and efficient one. But the only source for these peelers seems to be the occasional promotion from Sunkist or other citrus growers, and I've never seen where they could be bought in quantities of less than 1000. (Click on the image for a flash animation of this little wonder.)
