A common problem for parents is whether their children will accidentally discover unsavory content while online - an innocent search for "boobie joke" might get them more than they were expecting. There are lots of programs out there that purport to solve this, but the majority of them simply keep lists of inappropriate websites that you have no control over, which very often have political motives behind the content blocking. Enter a plugin for Firefox called ProCon which puts the control in your hands, so you can decide what is appropriate or not. ProCon allows you to block specific domains and URLs, block words that appear in the page itself, and add sites to a "whitelist" so that they're never blocked. While not the most powerful, it certainly is a step in the right direction and parents who are concerned about their children's viewing habits should definitely give it a try.
For the last two days the Firefox install on our home PC has been behaving oddly, specifically moving the arrow keys no longer moves the page as a whole, instead it scrolls through the text like in Notepad, MS Word or something. As it turned out I had inadvertantly turned on caret browsing/navigation where you can move around the page and select content with your keys rather than the mouse. Most likely I accidentally hit the F7 key which turns it on while I was tidying the desk at home, ironically I found out about it while cleaning my desk at work and wiping down my keyboard when I accidentally hit the relevant key. I can see how it would be beneficial at times but I wish there was a status display to say it was turned on/off to at least give a clue to newbies that it was at least possible, so they don't think they're going insane when their computer starts doing something funny. Doh.