Sources

Yahoo Library: http://developer.yahoo.com/ypatterns/

Thorough discussion (mostly about software dev't): http://hillside.net/patterns/

http://ajaxpatterns.org/Main_Page

Collection of articles: http://www.deyalexander.com.au/resources//uxd/design-patterns.html

http://designinginterfaces.com/ = O'Reilly book

http://www.welie.com/patterns/index.html

The Interaction Design Patterns Page: http://www.visi.com/~snowfall/InteractionPatterns.html

old: http://www.pliant.org/personal/Tom_Erickson/InteractionPatterns.html

2003 book: http://www.designofsites.com/pb/index.html

Jan Borcher's book page (and the book itself - A Pattern Approach to Interaction Design): http://www.hcipatterns.org

Experiences -- A Pattern Language for User Interface Design: http://www.maplefish.com/todd/papers/experiences/Experiences.html

This page on the IA Wiki: http://iawiki.net/WebsitePatterns

Not patterns, but 2002 data on instances of elements: http://www.webdesignpractices.com/index.html

gov pdfs: http://www.usability.gov/pdfs/guidelines.html

Blog on UI patterns: http://www.widgetopia.net/

GUI: http://www.guidebookgallery.org/index