This is the next version of Zen Coding. It promises to greatly speed up html and css coding.
This plugin fixes your css by adding the necessary browser version of yout css3 properties. If something is not needed anymore, it removes it. You can test it seperately here: http://prefixr.com/. Another thing I learned about is http://caniuse.com, check it out NOW!
This plugin dowloads frequently used files (jquery) or even zip files (wordpress) to the opened file or project directory.