There are plenty of CSS like styling frameworks knocking around but I quite like the hands off approach that this tiny library from Brent Simmons takes. Sure, it is primarily going to be used to apply styling but as it is simpler than that it could also be used to enable/disable features during development. Plus, it's drop dead simple and I am always a fan of that.
I haven't had more than a cursory glance at Go since it was released but I always enjoy learning approaches from other languages, maybe I should take a better look at it. It's always worth digging into a language which takes a different approach to what you are familiar with, you almost always come out of the experience a better developer.