This program evolved with my need for keeping a Diary, over the past twelve years. It is pretty stable, since its download statistics make me believe I have at least 300 users, but hardly anyone ever notifies me of a bug or a wish for more functionality. It comes with a complete manual, which is hardly ever needed because of it's intuitive user interface.
What do you get when you download Diary right here from the links below? No fancy install procedure, but just a simple ZIP-file. Unpack it in a fresh diary, and have fun! It is completely freeware, and if you want the sources, just download them...
For the sake of completeness, here's a table which features links to some of the recent versions, and a paypal link in case you REALLY like it: