Someone has registered dozens of Del.icio.us accounts to seed many of Del.icio.us' tagspaces with a specific URL in order to artificially inflate the apparent rank of the link, thus attracting as many click-throughs as possible (see below for a screen capture). While this "Del.icio.us bombing" seems to have been done as a practical joke (the URL in question leads to a near-endless stream of offensive pop-ups), the method could easily be used as a marketing tool.

This form of Del.icio.us spam is much harder to stop than previous versions, because multiple user accounts must be manually muted in order to ignore it. While setting up this type of spam method is a chore for the spammer, it even worse for the users--and as Star Trek puts it "the needs of the many outweigh the needs of the few." As I've mentioned in previous posts about Del.icio.us, a community-run filtration method (such as the one in use on Slashdot) would save the masses from being bombarded with unwanted information.

See below for a pic of the Del.icio.us bomb in action. The link, bookmarked by 81 people, has in fact been bookmarked by a single user with multiple accounts. It has been circulated to a variety of tags.