If you are a steady visitor of this blog, you should know I am a fan of flickr.com. Many of the photos shown here come from this site, most of the 365 too.
The main flaw of flickr is that it has become so popular that it is now too flooded, filled with pictures and videos of all quality. Thus it is not always easy to navigate good quality content, even though many efforts have been made, from explore pages to panda.
A very effective way of filtering the raw flow of data from flickr is to use the site flickeflu.com. You can browse the explore photos, let the site show you the most recent pictures selected in the explore flickr page as a slideshow, visit a photographer's page, share through a social bookmarking site, visit your own page and your own favourites, etc. It is like a new user interface of flickr! And I must say it has a beautiful dark skin.