Re-teach what you have learned by Blogging

A very effective way to internalize your learning is to teach it to someone else.
Blogging is a great way to share what you have learned and get feedback from others to corroborate and enhance the topic.
A blog is also a great way to:
Connect with like-minded people and share insights on topics relevant to your community.
Position yourself as a thought leader, or expert on a topic
Help others by sharing your experience and education.
Make a difference in a community that is important to you.

Blog sites that are given great reviews include:
Wordpress and Blogger (by Google) have been around the longest and are the most popular because they are functional, flexible, with a strong community base, and good security.
Other options are:
 Tumblr  -  popular for photo blogging and the ease with which the community can like and re-blog. Good for photos and visual aspects.
Posterous – popular for micro-blogging, and easy for beginners.With Posterous you cannot re-blog.

This blog is hosted through Google's Blogger.  I found these features user friendly:
There are many templates to choose from, and you can customize them.  It is easy to navigate and easy to edit.  Blogger is media friendly.  The community can easily add comments to the discussion.