Many people today use Google Closure Compiler to actually "compile" their JavaScript code. The advanced mode enables it to rewrite JS to better, faster and smaller JS-code that functions the same way as the original input.
Are there any good compilers out there for HTML/CSS? It could for example compress the CSS classes like a JS-compresser does. It could remove any divs (display: none;) that no JavaScript actually displays (display: block;). It could remove whitespaces. It could combine small images into sprites. It could combine files that are included on all pages into one file.
The list just goes on and on. Do you know about any good tools for this job? (Even if it only can compress CSS classes etc.)