Linux Search is a custom search engine that only searches dedicated Linux websites.

Google used to have a custom search for Linux (aka GNU/Linux) at google.com/linux but they discontinued it on the basis that it's normally enough to add linux as a search term. However, this custom search is useful:

• If you want to avoid spammy search results
• When searching for a rarely used term such as a model number - such searches often give hits which mention merely Linux in a sidebar or footer etc, but where the page itself is are not actually about Linux.

By narrowing the search down to only Linux-specific websites, these problems are avoided.