Another good system is
Skoach. I really liked it but it wasn't doing for me what I was looking for at the time. I might revisit it now that I'm starting this business and just use it for that instead of using it to manage my personal life.
It takes project management a step further and will take the list of tasks you have for that project, color code them by priority, and with one click it will put them on your schedule for based on wherever you have blocks of time open.
Its actually a program designed for adults with ADD. lol