I would like to see a line of products that look like children's toys, but are upon closer inspection actually things that you would not want your children playing with. The possibilities are endless—sex toys, drug paraphernalia, and so on. Here's a crudely-drawn example of one of the things that springs to mind:
What little girl (or boy!) wouldn't want a cute little toy like that? But, sorry Julie, this toy is just for the adults.
The only problem is that somehow naïve grandmothers would stumble across them and buy them for the grandkids, and then Mommy has to explain why Julie can't play with that toy until she's fourteen.
[Note: these products may actually exist, but I swear I just came up with this idea.]
Currently listening: Gotan Project—La Vigüela