A while ago, Al Nyveldt wrote a post on 5 things he loves about BlogEngine.Net  and I totally agree with him on all the 5 and more coming in the future releases,  Mads Kristensen too wrote and made a video on a the widget framework on a nice feature coming up in the next version of blogengine.net.

BlogEngine.Net is built to take advantage of standards, one standard I loved that is implemented in BlogEngine is the OpenSearch 
standard.

The cool thing about this standard is that modern browsers are able to detect it and have the option to add the search through the blog.

The opensearch standard is an xml document written in a special format you can see mine here.

And when I search through the browser I am sent to this :

So to implement opensearch in your site, (should have something to search in) you need to do these 2 steps.

1. Build an opensearch format xml file.
2. Attach the file from your homepage using the appropriate tag in the head section, like the following.

<link title="Amr Elsehemy's Weblog" type="application/opensearchdescription+xml" 
href="http://www.amrelsehemy/opensearch.axd" rel="search"/>

Thats All.