We find that most note-taking, project planning and business organization tools are too restrictive. They want you to organize your information in a certain way that may or may not fit your business or style. VoodooPad is a little personal wiki program that runs on your Mac and allows you to create almost any organizational system you want. You can keep notes, to-do lists, frequently used text and images, ideas and almost anything all together and linked to each other in a way that works for you.
The “Lite” version is free, and it may be all you need. It is packed with features and there is also a full and pro version if you want more power or to support the creators. You can read more and download it at FlyingMeat.com.