Why should I use diigo or similar bookmarking tools?

Bookmarking and efiling is essential in this ‘age of information’. I use diigo to file favourite sites using tags for easy retrieval. Before delicious and diigo, I added my most commonly used websites to favourites, but those favourites could only be retrieved from that computer. Now I use diigo because:-

1. I can bookmark interesting sites for easy, quick retrieval
2. Keeps me organised. As I am attending the ISTE conference at San Diego for the first time I am feeling overwhelmed about attending a conference that has 22,000 attendees and a multitude of presenters, so as I see interesting recommended sites and links, I am bookmarking them to diigo with an ‘iste’ tag. These include the conference program, the ning, social activities, interesting blog posts with tips on getting the best out of ISTE,  things to do in San Diego, transport sites etc. To retrieve all these, I simply search for ISTE in my tags and the list comes up.
3. Availalbe 24/7 and anywhere that I may be. My bookmarks and curated sites are saved in the clouds, so I just need internet access to find the bookmarks
4. Special interest groups can be formed in diigo – eg educators, global education conference,  digital citizenship etc. Many other people with similar interests,  are discovering some great sites related to  topics of interest to me and I can tap into their collective knowledge/research. Students in the Flat Classroom projects use diigo to share discoveries with their global groups.
5. Notes, highlights etc can be made on bookmarked sites.
6. Coolcatteacher (Vicki Davis) and other educators use diigo to post to their blogs. See eLearning and Global Competencies

There are many more ways to use diigo and a quick online search will bring up more. How do you curate or bookmark sites? What tools do you use?