When to leave your kids home alone?

At what age did you leave your kids home alone? When you were a child, how old were you when you stayed home alone?

I am an only child, so I either went to a friends house or had a babysitter.  My parents worked and I remember coming home alone after school when I was in third grade.

In Iowa, there isn't a state law requiring a specific age when children can be home alone. It is up to the parents to determine if their child is responsible or not.
 

I found some great information on this specific topic here. And I thought this information was important:

Tips for Parents

Once you have determined that your child is ready to stay home alone, the following suggestions may help you to prepare your child and to feel more comfortable about leaving him or her home alone:

• Have a trial period. Leave the child home alone for a short time while staying close to home. This is a good way to see how he or she will manage.
• Role play. Act out possible situations to help your child learn what to do.
• Establish rules. Make sure your child knows what is (and is not) allowed when you are not home. Some experts suggest making a list of chores or other tasks to keep children busy while you are gone.
• Check in. Call your child while you are away to see how it's going, or have a trusted neighbor or friend check in.
• Talk about it. Encourage your child to share his or her feelings with you about staying home alone.
• Don't overdo it. Even a mature, responsible child shouldn't be home alone too much. Consider other options, such as programs offered by schools, community centers, youth organizations, or churches, to help keep your child busy and involved.

At what ages did you leave your kids home alone?