Jreepad is an excellent free "personal database" program - it's a great way to organise all your personal notes, thoughts, tasks, recipes, memories...
What's more, it's open-source and programmed in Java, so that all may benefit from it! Much used on Mac OSX, Linux, Unix, and even Windows!
* A Jreepad file consists of a nice simple tree structure, and each "node" has an associated "article" - this can be plain text, HTML or tabular data.
* Nodes can be rearranged very intuitively.
* There's a very powerful and intuitive search facility to locate a piece of text in a subtree
* Hyperlink support
* Integrated Google search
* Load/save Treepad (.HJT) files, compatible with Treepad Lite (so you can share files with Windows users)
* ...and much more, of course.