Matt Cutts has unequivocally advised that web publishers drop rel=nofollow when linking to any of their internal pages.
This great SEO tip from Stoney deGeyter suggests how you can link to internal pages on your website by adding rel=nofollow attribute to links like “click here” or “read more” that have no relevant anchor text.
The Google Webmaster Guidelines document recommends using a text web browser called Lynx to help people visualize how Google spiders will see their websites.
Flickr has added nofollow for all hyperlinks (URLs) in photo descriptions. That means Flickr is no longer a lucrative place for SEO.