Web 2.0

1. Blogs

1.1. Wordpress

1.2. Blogger

1.3. Technorati

2. Podcasts

2.1. Podcast Directory

2.2. Digg

2.3. Learn Out Loud

3. Social Networks

3.1. Facebook

3.2. LinkedIn

3.3. YouTube

4. Wikis

5. Social Bookmarking

5.1. Del.icio.us

5.2. Digg

5.3. Technorati

6. Micro-Blogs

6.1. Twitter

6.2. Tumblr

7. ePortfolios