Logo is super cool, and I cut my teeth on it. There are a number of free versions available today. NetLogo is a neat version with parrallel programming tools built in.

But Scratch is what got my daughter excited.

Logo is a bit boring in comparison to Scratch. She has programs like TuxPaint to draw pictures with ("pictures" was the killer app when I was a kid, and logo was so much better at it than BASIC). Scratch provides a media rich programming experience.