Firefox users can select between several advertisement and script blockers for the web browser. From heavyweights such as AdBlock Plus (which has been heavily criticized recently for its business practices) to the powerful script blocker NoScript. Most ad-blockers are large in size and resource intensive at times, which can be especially problematic if you are running Firefox on a system that is not blessed with lots of RAM or processing power.
HellBoy Firewall, despite the name that suggests otherwise, is an ad-blocker for Firefox. What sets it apart from established extensions is the fact that it is as lightweight as an adblocker can possible get without sacrificing any of the blocking itself.
The extension has a size of only 30 Kilobytes for example while popular ad blockers for Firefox often cross the 700 Kilobyte mark easily. The core reason here is that the developer has created the extension with performance in mind.
That's great as it is using less memory when it is enabled in the browser and may also be a bit faster in terms of page loading times. Instead of relying on a large domain and IP address block list, the extension has been designed to use five hard coded blocking rules covering more than 7000 .com and .net domains taken from Easylist. So, instead of having to go through thousands of items to check, it is only checking five items in total.
How that works out? Quite well apparently. A quick test on several ad-heavy websites showed no advertisement at all on those sites. While I cannot guarantee that it will cover all ads that you may encounter on your journeys on the Internet, it seems to cover major ad providers and domain, and takes care of them.
There is a downside to that though, which you will notice eventually. The extension ships without preferences or an interface. The only thing that it adds to the system after installation is a button that it places in the browser's main toolbar. You can use the button to turn the functionality on or off.
A lack of options, whitelisting for example or adding additional domains or servers to the block list, is certainly a no-go for some users of the web browser who want more control over the ad blocking process.
Other users may even prefer to use it this way, as they do not have to configure anything at all. While they may run into websites where ads are still displayed, it is something that they may not mind that much.
Webmasters on the other hand may not like the approach at all, as it does not give users a choice whether to enable or disable the extension on their properties. While it is possible to turn the extension off when a respected or favored site is visited, it is unlikely that many users of the extension will do so as it is to much work to turn it on and off all the time.
If Adblock Plus or the ad blocker that you are using is bringing your computer to its knees performance-wise, you may want to give HellBoy Firewall a try to see if it resolves the performance issue for you without sacrificing the ad-blocking too much.
Update: The add-on disappeared from the Add-ons repository shortly after the review went online. The author appears to have relaunched it as BluHell Firewall. You can download the new version right from the website again.