Design Curate is a great site for browsing on a Saturday and getting inspiration. They host a collection of free and commercial resources for designers and have served over 3,084 design freebies to date. There you can find graphics for buttons, tables, menus, backgrounds, textures, and more. They have free and commercial PSDs available for download and many HTML/CSS code snippets for menus, galleries, and animations.
Design Curate also has a growing WordPress section that includes several free and commercial themes.
To get a wiki up and running you used to need to install Mediawiki and toil away for days configuring it... not any more! This plugin gives you *all* the functionality you want from a wiki, in WordPress!!!
Fully integrated with the SEOMoz API, complete with automatic links, sitemaps and SEO optimization of your WordPress setup - this is the only plugin you need to help you rank your site number 1 on Google - nothing else compares.