Firefox Developer Edition - Built for those who build the Web. The only browser made for developers.
Dr. Link Check - Broken link checker with malware and parked domain detection
WPMU DEV - WPMU offers WordPress Plugins, WordPress Themes, WordPress Multisite and BuddyPress Plugins and Themes.
BrokenLinkCheck - Free Broken Link Checker / Online Dead Link Checking Tool - find bad hyperlinks
MAMP - MAMP is the abbreviation for Macintosh, Apache, MySQL, and PHP. It is a reliable application with its four components that allows you to access the local PHP server as well as the database server (SQL).
DRKSpiderJava - DRKSpider is an open source website crawler (sitemap generator) and link checker. Features: