Some interesting, and sometimes counter-intuitive tips in here. A good checklist when optimizing.

jQuery plugin for making display text scale with your design.

"Contextual pagination" -- annotates the browser scrollbar with sections of a page, complements long/infitinite scrolling pages by keeping the user informed of location. Looks neat, the jQuery UI dependency is a bit of a bummer

Edit text fields inline, like how Flickr does

A bit of a hack, it hides the actual form elements, then wraps them in divs and spans, styles those up then uses scripting to handle the form interaction.

jQuery for iPhones

Nicely done

Find the lightbox that's right for you, with filtering by feature or JS library

Delay the loading of images until they are visible in the user's viewport for faster initial page loading. Smart.

With JSON support

Smarter Flash embedding using jQuery