Load Impact Tester

Is your website ready for the traffic you will get if your site goes viral? This webtoool will simulate visits by multiple visitors to see how many users your site could handle at once.
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Is your website ready for the traffic you will get if your site goes viral? This webtoool will simulate visits by multiple visitors to see how many users your site could handle at once.
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Very nice rich featured colour scheme picker.
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9 Nice high res backgrounds (up to 4000 X 3000) Courtesy of Garcya from Web Design Blog.
This extension checks all the links on a page and gives you a visual report of what’s working or not.
Features from the site:

This Web tool allows you to search for available domain names by entering a keyword or phrase which it will then use to look for similar or related terms. It then checks that domain’s availability, and then gives you a list of all available domains, related domains, as well as how often that term is searched for every month.
The aim is to get urls that will benefit from ‘type-in traffic’ For example, when someone types in ‘fastcars.com’ into the browser window instead of searching for it in a search engine.
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update -June 26: This fantastic service is unfortunately now only free for .net domains

WAVE is a web tool that analyzes any web page you choose, enter the URL and WAVE shows the original web page with embedded icons and indicators that reveal the accessibility information within your page.
For example, It’s very good at finding images with missing alt tags, a missed opportunity to add keyword to your site as spider food.
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Simply click to add, remove, widen or narrow your columns and margins, then set your type preferences and export the CSS
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The PhotoDropper plugin lest’s you easily and quickly add free photos to your WordPress Blog posts with 1-click! Once you enter a keyword for a photo “Photo Dropper Browse Photos” menu it will show you all the available photos matching that keyword, then all you have to do is select the size you want and the image will appear in your post along with links to the original site and license.
There is an option to use only commercially available photos if your site is a business.
The amount of Creative Commons images uploaded to Flickr daily is astonishing so this tool will become more valuable by the hour.