ithought is a personal thought manager, allowing you to create and store entries that can be linked together via keywords. Through the use of various modules, it is possible to do a number of things with these entries, including uploading to a website as part of an online journal. Modules can be written in C or in any scripting language. Modules are currently available to upload diary entries to kuro5hin, livejournal, and advogato.
(No, I didn't write it.)