I think it is definitely worth this extension. Any sort of How-To search at this point ends up linking to worthless Pinterest sites of pictures and broken links that may or may not have anything to do with my search (even if on the Google results page it seems they do). I keep getting bit by this, and I look forward to a FF extension too.
That extension is just a placebo. It doesn't exclude search results, it just hides them. If your search returns many unwanted results, enjoy paginating a handful of links at a time. It filters only web searches; news, images, videos, etc. are not.
I used and dropped it last year. Maybe it has improved, but I doubt it will ever replace the removed "block this site" feature Google had. That worked.
This is an excellent idea. For me, Pinterest ruins search in a few ways. First up. I don't have a Pinterest account. This means when I click an image result I can't actually get to the full-size image without logging in. Second, since all their content is stolen the original source of the image is pushed way down in the results (if it's in there at all). Finally, I get the feeling there are a lot of bot created Pinterest boards as images tend to be shown beside completely unrelated images.
This is not a big problem, but it is annoying enough that I downloaded the extension. I'd like to see a Firefox extension, too.
I have been making little JavaScript extensions to do things like sift eBay results and remove sponsored links from searches on some sites. None are mainstream, but they are used and useful.
From Chrome (and maybe Firefox) you can export an extension to a local folder and view the source. Also, many are on github that you can check out and play with. Find one that does something very simple and tinker, first just changing some text in it, then making bigger changes to get a feel for it.
