I've considered adding some basic minification for CSS and JS, however the topic gets complicated very fast. To do this properly you have to have full parsers for each type. For instance, in JS is is perfectly valid to leave off ;
at the end of lines, but the code will break if naively minified. HTML is even more complex due to issues with whitespace, and some IE-specific HTML comments.
Probably one of the simplest steps is to configure your web server to gzip encode HTML, CSS and JS. That will get you a significant amount of bandwidth saving. Beyond that you'd probably need to look into technology-specific compressors.