flickr.com is a great way to kill a day without actually wasting it. flickr is also a great way to share photos with friends and family. And there are many talented photographers who post their art to flickr for all the world to enjoy. Unfortunately, there is a lot of noise and distraction on a flickr page.
blackr is a bookmarklet I created which you can put in your browser's bookmarks bar. When you are on a flickr photo page or one of the "All sizes" pages, you can click the bookmarklet and it will hide everything on the page behind a soothing black canvas except for the photo.
Optionally you get a white border around the photo. artissoft told me that exactly 52.3% of all photographers prefer 12 pixel wide white borders around their pictures and I can understand why. Although I prefer the border version, there are a few pictures that look better without the border. And then there are photos that look better on a white background. Mostly with a black border, but again, there are exceptions. So, while blackr is active, you can toggle the four versions with your keyboard. Yeah, hotkeys!
I found blackr to run best with Safari and Camino. Firefox works perfectly well too and IE6+ works nearly perfectly. Guess which one was hardest to tame.
To see how it all works or to modify blackr (ipernity anyone?), get the complete zipped source here. Installing blackr locally is also very easy, but you will need a little Javascript knowledge. I have created a forum for blackr.
After installing blackr why not look over your Favorites again on black or on white.