Shares of Build-A-Beat Workshop (NYSE: BBW) have been fairly lackluster performers since the company's IPO in 2004, but a new concept store called Ridemakerz could change all that, as Build-A-Bear owns 25% of the new venture.

Build-A-Bear has about 300 locations globally, offering children and their parents an opportunity to customize their own teddy bears. Ridemakerz, whose first location just opened last week, will offer fathers and sons a chance to build their own toy cars. According to the New York Times, "Customers select a chassis type (street or monster); body styles (stock or custom, a Ridemakerz brand hot rod, a Ford Mustang GT, or Dodge Ram pickup, to name a few options); paint schemes; sound effects (for example, sirens or race sounds) and style of locomotion (free wheel or radio control) ... After the 10- to 12-inch cars are assembled, there are ample customizing and accessorizing options: tire treads, grille guards, side pipes, snowboard racks and decals. Mr. Andreini estimates that a fully tricked-out vehicle will run about $75, including $25 for radio control. For the budget-minded, there's a stock tuner car for $12."

If this does catch on, and it seems likely that it will, the growth could be explosive. Build-A-Bear grew from one store to more than 300 in ten years and, with the support of Build-A-Bear already there, Ridemakerz could much more quickly.

With the huge popularity of NASCAR and cars in general, Ridemakerz could be the catalyst for shares of BBW to rapidly gain in value. The shares are trading right around their price from a year ago, indicating that much of the upside of Ridemakerz is not yet priced in.

To learn more about Ridemakerz, see the company's website.