iUI is a framework consisting of a JavaScript library, CSS, and images for developing iPhone webapps.

Create interactive versions of your static layouts without coding.

Mockingbird is an online tool that makes it easy for you to create, link together, preview, and share mockups of your website or application.

To be good user experience folks, we need to crack open some psych 101 textbooks, learn what motivates people and then bake these ideas into our designs.

Usable websites offer great user experiences, and great user experiences lead to happy customers. Delight and satisfy your visitors, rather than frustrate and annoy them, with smart design decisions.

Iplotz allows you to rapidly create clickable, navigable mockups and wireframes for prototyping websites and software applications

If you design user experiences for standards-based websites and applications (i.e. those built with XHTML, CSS, and JavaScript), there are several great reasons for adding XHTML prototyping to your UX tool kit.

Pattern Party is a a place to share your screenshots. This site is geared towards sharing and storing inspiration, critiques and comments on user interfaces.

Web Visions 2007 Improving Interface Design Workshop on Slideshare

Nate Koechley and Yahoo are on to something here. It's just not realistic to say you either fully or do not fully support support a certain browser.

Screencasts of the new Joyent 2.0 UI. Makes me want to use this product just for the interface.

User Experience Comes in Threes