I learned of them when I read about their service in the MIT Technology Review several weeks ago. It’s by invite only, but I wrote and told them that they had to give me an account because last September I was emailing tech-savvy friends to ask if anyone could design a service exactly like this. I was willing to pay for this — like flickr or Mars Edit — but diigo is in fact free. No one took up my offer back in September, but by cosmic coincidence some electronic engineering professor geek at Berkeley was dreaming about the same thing and designed it.
What it does is this: you read something on the web, you bookmark it using diigo.com (you do need to install a little diigo bookmarklet on the toolbar). You assign a tag to it (if you want), or several. Then, you can literally underline the passages that intrigue you, and — this is the cool bit I’ve been waiting for — you can add a “sticky” note (just like on flickr) that associates with the part you’ve just underlined. When you look at your bookmarks, the list will show you how many annotations you have in each article you’ve bookmarked, and you can then expand that list to show you both the underlined bits as well as your “notes.”
