I've been using del.icio.us since 2004, and it has served me well. For those who still haven't tried it, it's basically a bookmark manager with a social twist. You can get a (nearly) real-time list of everyone's PHP bookmarks, everyone's MySQL bookmarks, my bookmarks, or the blogs I read.
At the bottom of each page, there is a convenient link to an RSS feed for that page. For example, you can get a feed of the blogs I read. There's only one problem - the feeds are limited to 30 items. That's why the list of blogs on my web site is truncated. A few people have noticed this, wondering why they're not on my list. Of course, I can fix this problem easily enough - I just need to start using the del.icio.us API.
This limitation isn't as easy to work around in other contexts. For example, the PHPSC Library is an organized collection of links related to PHP security. In order to keep the library current and relevant, we aggregate the bookmarks of the various members using del.icio.us. Unfortunately, if a member adds more than 30 resources to the library, some are truncated from that member's feed. The API requires HTTP basic authentication, so that's not a good solution, because I don't want to ask members to share their access credentials.
It's still possible to work around this. I can revert back to the days of screen scraping (which would be easier if the pages were valid XHTML), but doesn't that seem lame, considering RSS and friends are supposed to eliminate this need? I could use a tag naming scheme that uses a counter to split a tag into groups, so that no single tag has more than 30 items. There are probably a number of other hacks that would solve the problem, but none seem particularly elegant.
Hopefully I'm just missing something obvious, but my quick search of the del.icio.us mailing list uncovered this thread that mentions browsing del.icio.us directly as a solution. Ugh.