Open source library that uses JavaScript and SVG to render graphs and visualisations without a plugin. There are some lovely examples of what you can do with it: graph pr0n.

"Without much conscious thought, most of us have built identities across the web. We've filled in profiles, uploaded photos, videos, reviews and bookmarks. The Ident Engine uses semantic web API’s to bring together these web footprints." Interesting idea: allows you to publish a 'lifestream' from your activity on various social websites on your blog, but currently requires a fairly good knowledge of javascript/jquery to do so.

This looks like an interesting project. I confess that I've always had trouble wrestling with floats.

This is incredibly cool: generate sparkline graphs using only jQuery and CSS. I need an excuse to use this somewhere.

Useful plugin to list Twitters on your site if you have a static page.

Javascript live expansion and contraction of thumbnails. Looks pretty slick, but could get a bit busy with a lot of thumbnails I would think.

Interesting technique for displaying images overlaid on the webpage, avoiding any width limitations of your layout.

Nice Javascript library to make mouse-over information popups