Kod is an open source programmer's editor for OS X.
While still very new, the program already has syntax highlighting support for more than 65 languages. Not enough? The highlighting is implemented through CSS 3, so in theory can be edited or extended to suit your needs (although it's not entirely clear how this works yet).
And the interface doesn't only feature tabs, so you can have multiple files open at the same time. These also have Chromium-like functionality, where the tabs can be torn off and moved between windows.
The program has been written from scratch using the very latest OS X 10.6 APIs for maximum OS integration. And it's designed for speed, with just about every action distributed across all available CPU cores for the best possible performance.
Kod is a beta, however, so still has its problems. It allows you to edit remote files over HTTP or HTTPS, for instance, but, well, can't save them (oops). Still, there's plenty of promise and ambition here, so if you might be interested in a new editor sometime soon then this one is definitely worth a look.