Here is a list of software I use for development:

• MAMP
• Textmate - many great bundles that help speed up development time. 
• Vim - used on the server. Not as productive but still learning. Also great for large files and performing macros on those files
• TextWrangler (For those damn Japanese encodings not supported in Textmate. Also used for comparing files.
• Sequel Pro (Fastest way to connect, import/export data, query, whatever for mysql)
• GitX (customized version from GitHub)
• Google Chrome (fast, no nonsense browser)
• Firefox (Firebug for debugging JS, and working with CSS, rikaichan for japanese, and useragent plugin for working with cell phones.
• iTerm - works slightly better than terminal - just for full screen, and bookmarks
• Snippets - I am using the version before it became a paid app. Works good enough for me
• Evernote - used to keep notes on dev and other stuff
• Taskpaper - easy to use todo list based on text files
• Fake.app - used for automating browser based testing. It does not take the place of cucumber, but can be to see exactly what is going wrong in the browser. Can be useful for testers who are not familiar with code