I use AVG free for my virus protection which is great. They recently (okay, it's been months now) started offering a link scanner which scans the links that come up in search results. It scans each link and assigns it an icon: green, yellow, or red depending on its safety. I liked the idea of this, but it slowed down the loading of search results for me. I have 256K DSL . . . so speed is rather important.
I decided to try the Firefox addon Web of Trust (WOT), which is similar to AVG, in that it rates links in search results. The difference is that where AVG's link scanner actually scans each link, WOT rates links based on actual human review of the site. Who does this reviewing? People like you and I. When you download the WOT Firefox addon, you sign up to become a member of the WOT community. You can rate websites you come upon that have or have not been reviewed. One thing I really like about WOT is that when you do click on a site that is rated as potentially dangerous, rather than going directly to the site, you take a detour through WOT where you can give permission to continue on or stop. We all miss-click, so I like this feature.
So, I know that these two applications aren't completely anologous, but they have a similar goal: to help the user surf the internet with increased safety. The applications go about this goal in two very different ways. AVG has the advangtage of scanning in real time, which means that it can pick up threats that may not have been at a particular site a minute ago. WOT, on the other hand relys soley on the ratings of other computer users. So, there is a degree of human error here. But, because it is open to many users, errors can be caught and fixed. Humans can also recognize unsafe sites that a computer may not. For instance, a website may not have any spyware or virus threat, but may be potentially dangerous in another way, like practicing illegal or deceptive business practices. This is where WOT is helpful.
I currently use WOT. It fits my current needs. It doesn't take long to load a search with the WOT ratings as well. As, I specified earlier, AVG's link scan did take too long for my internet connection. I think both applications are great. Any computer with an internet connection should have protection like this to aid users in safe surfing.