Useful jQuery Plugins

I use jQuery pretty much every day at work, and in personal projects. I love the way it allows me to add rich functionality and effects to my projects, without much hard-core coding (well, unless I'm trying to be a smart-arse!).

So in true spirit of the Blogosphere, I thought I'd compile the top 10 list of my current favourite useful jQuery plugins...

1. Dimensions - This is one of the best. It extends jQuery with dimension specific methods. With it, you can get dimensions (height and width) of the window, the document, and individual elements, and find the co-ordinates (offsets) of any element in a web page. VERY useful.
2. Cookie - I use this one quite a lot, it makes manipulating cookies a breeze. Go get it!
3. jQuery UI - This is really a collection of plugins rather than one (but you can create your own build so you don't have to include the whole collection), but highlights include a variety of visual effects, including Fold, Slides, Explode, Pulsate, Puff and more, as well as some really slick ui elements such as a rather tasty SplitPane and Drag and Drop behaviours. Nice.
4. Media - This is a very cool one, it allows for unobrusive embedding of media including Flash, Quicktime and Silverlight into documents. Highly recommended.
5. labelOver - Another one in my regular jQuery toolkit, this allows you place the label over the input field, using CSS. It is based on a very good article on A List Apart about Making Compact Forms More Accessible
6. Validation - Anyone involved in the development of web applications needs a good validation script, and this is a great jQuery plugin that does just that. I hate ugly forms and JavaScript alerts, which is why I can't code a form without at least considering using this plugin. In short, don't leave home without it!
7. tableSorter - Sometimes, you can't avoid using tables, particularly for displaying data, and this plugin allows for all sorts of table tomfoolery, from basic column sorting to appending the table data using Ajax.
   
8. Form - This useful plugin lets you enhance forms to submit using AJAX. No special mark-up required, just include the plugin and write your callback. We like it!
9. Field - If you need to manipulate form fields beyond the standard val() method, this is the plugin for you!
10. XML to JSON - This is a cool utility if you work with Ajax and XML documents. Does what it says on the tin!

I could have easily made this a top 20 list, as there are so many good plugins out there, but then I would'nt have enough for my next list, but I hope you found at least one useful addition to your jquery library.