Google has finally open the Google Chrome Extensions for everyone on Linux and Windows. Mac users however have to wait as it is not yet available for them just yet. Earlier extensions were available only for developers. This launch is one day ahead of what was expected.
There are quite a few extensions available at the moment from Google GMail Checker, which displays the number of unread emails, to Chromed Bird, which is basically a twitter client. However, one extension that is sorely missing is AdBlock.
To install the extension, all you have to do is go to https://chrome.google.com/extensions/ or simply click on the "Jigsaw" at the bottom right. That will take you to the Google Chrome Extention page. You can then install all your favorite extensions from this page.
If you don not have Chrome (not Chromium) in your Ubuntu or Fedora system, you can see this guide.