Four Seconds - A timer and a simple rule: stop it at exactly four seconds.
GCompris - Educational Game for Children 2 to 10 years old.
Wikids - An encyclopedia that talks to your kids
Tux Paint - Tux Paint is a free, award-winning drawing program for children ages 3 to 12 (for example, preschool and K-6).
DragonBox Numbers - Teach kids about numbers with an easy and fun game
Etoys - Etoys is an educational tool for teaching children powerful ideas in compelling ways.