One of the online services/applications that has wiggled its way in to my near daily usage is del.icio.us. The concept, like most good ideas, is pretty simple; you save your bookmarks to a remote server and so does everyone else.
What makes del.icio.us special is that everyone else using the service does the same. Each user has their own page of links, each book-marked URL is assigned one or more ‘tags’. These define what the targets contents are about (think categories such as programming, humour etc) and allow easy access to related sets of links. You can also add an extended comment if you like.
The front page is a rolling collection of the most recently added bookmarks, if you wanted you could just leave this page open as a source of inspiration. Given half-an-hour your bound to see something of interest. What makes it easier to find items of interest is that the darkness of each links background is based on the number of people that have book-marked it using the service. The darker the background the more people that have thought it worthy of note. The community aspect of the site is what gives it a killer edge for me, i don’t get to speak to peers in some of the subjects I’m interested in but with a couple of feed subscriptions i can get an idea of what they are looking at.
Add to this the fact that you can get RSS feeds of pretty much anything you want (tags, peoples bookmarks, peoples specific tags) and its a great service, worthy of an evaluation.