Data driven simple solar system model.
Mainly good because it has a RaphaelJS gradient morpher I built
The libs directory also has some cool stuff.

A simple clone of the BBC News' slideshow image. Designed to be populated with a list of images from a server side language like php, the slideshow auto starts, has navigation and even works in IE6. Prototype and scriptaculous required, though you should be able to use moo.fx.
Prototype was patched with the code from Nick Stakenburg as Prototype has decided to support the bubbling event model and it's nigh on impossible to work it out for all browsers.

Version 0.1 of a quick and dirty hack to give you a translation of highlighted words via Google Translate.
Due to cross-domain scripting issues this has to currently be done in two steps. Submitting the data for translation with a bookmarklet and then screen scraping the result. I did mention this was a hack.
Currently supporting translation to English, and prompting for translation into Swedish

To use it you need to host the php script somewhere - the bookmarklet currently looks at localhost (most oses will allow some kind of personal web sharing, turn it on, dump the file in there called "proxyTranslate.php")
Then these bookmarklets will work for you.