Just seen a tweet from @thomasfuchs (creator of script.aculo.us, Zepto.js and more) explaining why he loves MacVim
Now wouldn't this be a nice plugin for ST2!
EDIT: Seems the VIM plugin is already on GitHub github.com/skammer/vim-css-color
Someone tried. Unfortunately, there's no api to set the background color if the color is not in the tmTheme. So I don't know how well this plugin works. github.com/a-sk/livecss
shame it would have been nice to try this out