If you have a Google / Gmail account and stay logged in, Google has provided a fantastic tool for blocking those websites or domains that never return anything good or trustworthy.
Just follow these steps:
- Go to www.Google.com.
- Click the "Sign in" button at the top-right corner and sign in with your account.
- Go to http://www.google.com/reviews/t?hl=en
- In the first box, enter: http://wikipedia.org
In the second box, enter your reason for blocking the site.
Click the "Block site" button.
Within a few hours no Wikipedia results will show up in your Google search results. Sadly, this only works if you are logged into your Google/Gmail account.