i use
Onstage and love it. it's free up to 20 projects. i like it very much.
i also use Freemind to map out projects in all their detail, but i really needed something that would help manage ALL the projects from one place, and Onstage is perfect for that. my favorite features are the ability to set milestones for projects, and also that every task item has a deadline, so you see everything that coming up in the next X days.