Intego ContentBarrier X5 sets itself the tricky task of restricting access to undesirable internet content for children and employees, while allowing them to browse the harmless stuff.

It is set up by the administrator for each user through a straightforward interface that offers more granular control over types of content than the OS X Parental Controls.

Websites can be excluded by category (for example, sex, alcohol, jobs or religion); chat can be blocked when key phrases appear; and it's possible to ban games, or to restrict total access on specified days and times.

The administrator can instruct ContentBarrier to record what's on the user's screen at preset intervals, record keystrokes and much more.

However, while ContentBarrier X5 proved effective at blocking pornographic sites, its performance in other categories was patchy.

It didn't take us long to find out how to make gin at home and build a bomb, visit an online gun shop, log on to our account with a well-known bookmaker, meet local singles and watch a video of Saddam Hussein's execution.

It also denied access to some innocuous content (we couldn't Google for 'films' or read about iguana reproduction), and it wasn't hard to find a way around some prohibited searches.

If porn's your main concern, consider this app. But don't expect a panacea for all internet ills.

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