CSS and JavaScript development bookmarklets
I ran across this commentary by Simon Willison on using bookmarklets to experiment with CSS. It points to Jesse Ruderman’s excellent collection of bookmarklets, which includes some great examples of what a line of JavaScript can accomplish.
The Web development section includes features like test css, which lets you type CSS rules to apply to the current page, and edit css, which lets you edit the current page’s styles and see the results in realtime. They both work on Mozilla browsers only, but it’s worth installing Firebird just for these – they’ll help greatly with my next CSS project.
There are also several useful bookmarklets for script developers: You can open a JavaScript shell that has access to the current page and view the scripts and variables on the current page. Be sure to check out the other categories of bookmarklets, such as the comprehensive list of search engine tools.