If you’re not using Sass in your projects you should drop everything, read about it at http://sass-lang.com/ and start using it in your projects immediately. I’ve been using Sails.js a lot lately and enjoying it immensely. Unfortunately while it supports Sass’ cousin, Less, you have to make some configuration changes to get Sass to work.
By default Compass will place the .sass-cache folder in the project root directory. I prefer to keep all caches and temporary file builds for my projects in the .tmp folder.