A calendar and journal
* The calendar shows the current and upcoming weeks rather than giving me a pointless week or month view which become increasingly useless toward the end of the time period in question.
* My appointments are shown in a list so I can see the next ten or so appointments regardless of how far into the future they are. Additional appointments are just a button click away.
* It has support for a daily journal wherein I keep track of stuff I did. Some people probably aren't this anal, but I find it to be interesting and useful. Even more so when I eventually add searching support.
* It's data can be shared between computers by instructing Jikan to store its files in your Dropbox folder (or any other magically mirrored directory). Jikan will detect when files are updated and reload things appropriately. I regularly have it running on at least three computers.
* It syncs your appointments out to a Google Calendar. At some point I'm going to implement bi-directional syncing, but for now if you create (or update) an appointment in Jikan it will get written out to your Google Calendar (assuming you log into your Google account when it starts up).
I've been using it for half a decade or so and find it to be pretty functional. A few things to note:
* Right click on a date to create a new blank appointment entry for that date. Then edit the appointment below to fill in the details.
* The date and time parsing code is fiddly. You have to enter in "HH:MM xM" exactly or it will fail to parse. In the future, I'm going to write a graphical widget for setting the date and time.
* Right click on list items to delete them. Events do not automatically expire after they have passed, you have to manually delete them. Perhaps someday I'll automatically archive them in the journal.
* It used to also have categorized TODO lists but I nixed those in favor of using separate TODO software. Jikan now focuses on maintaining appointments that have a date and time and on recording a journal of your daily activities.