What would be a great toy idea?

My cl is doing a project where we have to think of a great product that would sell, we're doing this as a presuasive peice and we have to brainstorm a toy that appeals to most age groups. My group thought up and wanted to stick with something like a X-box Portable but my teacher said we cant use the name xbox since it was already patented and copyrighted. What type of toy would be the best?