Really good link Madness. Despite it's title, this really serves as a way of teaching (or reminding) writers of how important conflict is. This can be anything from the most extreme example -- torture -- to something mundane, like a literal roadblock. Not just reaching goals, but being changed by the path to get there.
This here is one of my favorites, really in depth and just a great source of wisdom on a variety of topics. Even though it's technically devoted to fantasy, any writer working in any genre can benefit from "Limayaael's Rants".
http://www.forresterlabs.com/limyaael/titlelistall