We love these tin replicas of a Czech car called the Tatra made by a Czech company called Tin Toys Kovap. Use a key to wind it up and watch it go. The best part- the bumper keeps it from falling off tables. Choki-ori is the new paper craft from Japan. It's a great introductory activity for ages 5 and up who aren't quite ready for origami yet. Just cut along the lines and fold to create these farm friends. More fun than a regular puzzle, Nueve is a set of handcrafted wooden cubes that can form billions of patterns. Designed by newartifacts in Uruguay, they're made of hardwood and silk-screened in red.
There are loads more unusual things to see at Brooklyn 5&10.com, many of which would be the hit of a birthday party.