Stage Builder

Super Smash Bros. Brawl will allow you to create custom stages. First, you select the size of the stage. Then, you pick a background and a music piece to play on it. Then, you set the terrain. You can send one stage per day to Nintendo. In addition, Nintendo will offer a "stage of the day" that you can battle on for one day only. You can also send stages to your friends, and they are compatible with SD cards.