Junior's back in school, and you're... back at work. What's he doing in the hours when no one's there to watch him? Well, if he's like any other kid, he's online, trying to figure out how to make a pipe bomb just for kicks.

What do you do about such a situation? My kids are three years old and four months old, so I haven't gotten around to worrying about unsupervised computer use yet, but eventually I will. Here's what the experts think about it.

• Virtually everyone suggests a content filter like Net Nanny or CyberPatrol, particularly for younger children. It's important that you don't try to "sneak" this by them (they're too smart for that), but rather tell them you're filtering out objectionable content ahead of time.
• Beyond filters, there is monitoring software that can tell you exactly what the kids are up to online. You can try something like eBlaster, which sends you copies of every email they write and every chat session they have. It may sound very Orwellian, but it's also potentially not a bad idea.
• Finally, you can simply disable access to the computer when you aren't around. Simple password protection is one way. Software that locks out access to the Internet during certain time periods is another (most routers have this functionality built in).

As a free-will kinda guy, I'm not sure how I feel about such measures, but I just haven't gotten to that point in my life as a parent yet. I guess it depends on how the kids turn out, no?

So while I wait eight or ten years or so to find that out, maybe you readers can offer some advice. What monitoring/filtering system do you use at home, if any? And how well does it work?