Ancora qualche motore per il social tagging (il fenomeno è in rapida espansione e la scelta adesso si fa davvero ardua…):
Furl is a free service that saves the important items you find on the Web and enables you to quickly find them again. Furl archives a personal copy of every page you save. When you want to recall it, you can find it instantly by searching the full text your archived items. Each member has a personal archive of 5 gigabytes (GB), large enough to store tens of thousands of searchable items.
Furl also offers the best ways to share the content you find on the Web. Send a daily email newsletter of links to friends and colleagues, use Furl to generate RSS feeds for your links, or integrate them quickly and easily into an existing Web site.
de.lirio.us can store and organize your bookmarks for you, filling in for your browser's bookmarks feature. Since you won't be using "Add Bookmark" anymore, you'll need a new, convenient way to bookmark pages. Bookmarklets like these will help:
post to de.lirio.us
post to de.lirio.us (pop up)
You can drag them to your browser's bookmark bar (if it has one) or put them in its bookmark menu.
reddit is a source for what's new and popular on the web — personalized for you. Your votes train a filter, so let reddit know what you liked and disliked, because you'll begin to be recommended links filtered to your tastes. All of the content on reddit is submitted and voted on by users like you.
Simpy is a social bookmarking service. With Simpy, you can save, tag and search your own bookmarks and notes or browse and search other users' links and tags. You can be open and share your links with others, or keep them private.
Simpy also helps you find like-minded people, discover new and interesting sites, publish your bookmarks, detect and eliminate link-rot, etc.
Spurl.net is a free on-line bookmarking service and search engine. It allows you to store and quickly access again all the interesting pages you find on the web from any Internet connected computer.
With Spurl.net you will never have to lose a good link again. You can search your links, notes and in fact the entire text of all the pages you've ever "spurled".