Scuttle is a free open source software also modeled after Del.icio.us.
The idea is that since Google indexes many Scuttle sites, if your website is listed on them, it will increase the ranking.
Of course, not all the people who have Scuttle sites want them used for publicizing any old site - so many of them have "do not follow" code on their sites, which keeps the sites on them from being re-listed by Google.
No worries, Scuttlr will automatically detect whether a Scuttle site is marked "follow" or "do not follow" and only submit your link to the sites where it will do the most good - for you, anyway.
Many Del.icio.us tools also work with Scuttle, which can make it attractive to developers familiar with the larger platform but looking to implement it for personal or small community use.