Kod is a programmers' editor for OS X
Source available at http://github.com/rsms/kod
Goals and features
Fully concurrent — loading files, syntax highlighting, etc is distributed across available CPU cores. Minimal waiting time.
Integrated scripting environment based on Node.js.
Written from scratch with modern OS X 10.6 APIs providing maximum OS integration while avoiding reinvention of the wheel.
Sports a Chromium-like user interface where tabs can be torn off and moved between windows. More Info »
Allows editing (although not saving, currently) remote files accessible over HTTP or HTTPS.
Styling of the editor (not only the syntax highlighting) through regular CSS 3.
Comes with support for over 65 different languages/syntaxes which can easily be edited or extended (Kod uses the same format as GNU Syntax Highlight).
And more awesome features...