Glubble is a parental control plug-in developed by Glaxstar for the Firefox browser. It allows parents to control a list of domains that their kids can visit. Glubble lets kids to see family friendly parts of the web, based on selections made by their parents. It is customizable for each family member. When parents install Glubble, they create logins and passwords for each of their family members as adults, young children, or pre-reading children.

Source: TechCrunch

Above: Glubble Screenshot -- #1