Dance Dance Revolution

What it is: A soft plastic mat you plug into a Nintendo GameCube. You dance on the mat prompted by what's going on onscreen.

The games: Best for young kids (5 and up) is Dance Dance Revolution: Mario Mix; it follows the cartoon character Mario as he tries to retrieve his lost Music Keys, which will restore peace -- and rhythm -- to the people of the Mushroom Kingdom. Kids are challenged to dance in sync with a song as the right moves flash on the screen. There are also head-to-head (well, toe-to-toe) dance-offs against other characters in the game. Other Dance Dance Revolution titles with more of a music-video feel are better for kids 10 and up. Three-year-olds will want to dance on the mat but probably won't have a clue how to make things happen onscreen. At age 5, kids really start to figure it out and don't want to stop.

Why it's cool: Kids love to dance, and these games give them a fun excuse to just move and squirm and squiggle. Dance Dance Revolution has spawned a sort of electronic sport of its own, with competitions in arcades around the world. Guaranteed to make you sweat and your children pant.

Price: $50, including dance mat. Requires Nintendo GameCube console, which goes for around $100. Buy it!