This was originally meant to be included in Los Increíbles (2004). The scene was ultimately cut and then expanded into a short and specially made for the DVD release of Los Increíbles (2004).
In "The Incredibles," Kari says she plays Mozart for Jack Jack because "Mozart makes babies smarter." When Jack Jack bursts into flames, the dramatic music in the soundtrack is the "dies irae" from Mozart's Requiem Mass in D minor (K. 626).
A short list of Jack-Jack's powers portrayed in the short include but are not limited to: shape shifting, matter-eating, anti-gravitation, floating, hovering, flying, teleportation, molecular phasing through objects, telekinesis, super strength, spontaneous combustion, laser-projecting eyes, and indestructibility.
When Jack-Jack is first shown playing, the toy at the far right of the screen is the Pixar trademark ball from Luxo Jr. (1986).
The gadget Rick uses to erase Kari's mind is used again on the opening scene of the sequel "Incredibles 2".