Bookmarking and annotating

Today I came across this post by Robert which I definitely want to remember. I had no idea that there were tools like the ones he mentions below, which let you bookmark, annotate and share web pages.

"...I wonder if others have experience of these:

http://trailfire.com/

http://stickis.com

http://fleck.com/

http://sharedcopy.com/

http://info.jkn.com/

http://www.mystickies.com/

http://drawhere.com/"

I have had a quick look at some of them and they look really interesting. I'd like to explore this some more to see how they compare with del.icio.us, Diigo and SimplyBox.