As the topic states, you can post your own ideas for new Mario merchandise. I'll start;
FLUDD: As seen in Super Mario Sunshine, FLUDD is now available on toy store shelves everywhere! It's basically a water gun that straps onto your back. All you have to do is pull back the two handles, and you'll be squirting water quicker then you can say "Mario". The box also includes a hover nozzle, which you can use to hover in the air for at least 5 seconds, but only if your under 200lbs. Nintendo is also experimenting with a rocket nozzle that can shoot you 20 feet in the air, and a turbo nozzle that can launch up to speeds of 32 MPH(42 in water). Fludd comes in 3 sizes (small, medium and large) and will retail at a price of $59.99.
Mario Bobble heads: Highly detailed bobble heads based on the popular Mario franchise (obviously). These awesome looking bobble heads will be sure to make any washer or dryer a lot more exciting! Series 1 includes Mario, Luigi, Peach, Daisy, Bowser and Donkey Kong. Series 2 would include Wario, Waluigi, Koopa troopa (red and green shelled), Bowser Jr. and Toad. Each one costs $4.95.
Mario chess set: Since Nintendo knew a "Mario chess" game really wouldn't catch on, they decided to release a Mario themed chess set out to the market. As an added twist, each figure has a button that, when pressed, will make them say a phrase. Each character comes equipped with 3 phrases. The chess set comes with 32 pieces, one board and costs $12.05