Blogger Leo Babauta rounds up five great GTD applications for the Mac, then finishes off the post highlighting his own homespun setup, which uses a combination of the Quicksilver append action and the text-embedded desktop tool, GeekTool. When all is said and done, this setup will allow you to quickly and easily add tasks to your to-do lists through Quicksilver without losing focus on what you're doing, then display those items on your desktop for easy reviewing with GeekTool. It's a simple but effective setup, so if that sounds appealing to you, head over to Zen Habits for a full introduction.
5 Amazing Mac Apps for Getting Things Done (Plus a Custom-Rigged Setup) [Zen Habits]