[roryokane]

I have tried out both Less (http://lesscss.org/) and Sass (http://sass-lang.com/), but not used either in a big website. It looks like Sass is better – it is more powerful in that it supports more functions and you can optionally use an alternative, less-redundant syntax with significant whitespace and no semicolons. The 2009 post http://nex-3.com/posts/83-sass-and-less by the creator of Sass compares the two, and the two deficiencies in Sass mentioned in that post have since been fixed. From what I can tell from looking quickly at the Less website, it hasn’t really improved since I last saw it. I’m using Sass for my very simple personal website, and it works fine for me.