Best Web Design Tools for OS X?

For a long time, I've done web design and web front ends for a few small local businesses. However, as surely at least some of you will know, web design can easily be a confusing, tedious, time-consuming process. Thus, I've begun a search for the perfect (set) of web design tool(s) for OS X.

Almost a year ago, I began using Sublime Text. Its autocomplete feature is brilliant, as is the clean design. It's a basic tool, though, and many editors offer far more features.

What are your favorite web editors/tools for OS X, web designers of The Verge, and why?