I remember once in high school (lets call this 2003/04) I bought an 8.5x11 paper calendar. This was after the age of PDAs (indeed I think I had a PDA at that point), and damned if it wasn't the best calendaring experience I'd ever had. I kept track of things, I knew what was going on beyond the obvious, it was pretty good.
Other than that, I've not really (until now) used a calendar in my day to day work. I have a good memory, and pretty simple commitments, so it's never been a big deal, and most calendaring tools kind of suck. Actually, really suck.
Now mostly, I could care less, except I have this job now, and the scheduling is really complex. I have meetings with clients, I have intra-office meetings, there are things I have to schedule with other people. It's intense. So I've been trying to figure out what to use, how to connect with other calendars, and generally how to make it all work. I'll tell you what my uneasy solution has been, but I'd love to hear what you use.
Chandler
The Chandler Project is a really pretty darn interesting open source program. It's written all in python, it's designed for collaboration and uses all the open standards. It has a really interesting and useful tagging system. It has a feature-loaded (and not annoying!) web interface that compliments the desktop experience.
And despite this it's kludgey. It's not peppy, it uses it's own paradigm, and like all multi-platform software, it ends up looking just a bit foreign on all OSes (though I've not worked very much with it on linux, so to be fair, it might seem less out of place.)
Still, Chandler has become my "home" Calendar Application. There's something nice about the way that it syncs to Chandler Hub, and all the cool things I mentioned above. And I like it's dashboard a lot. When I started doing this job, I went from being able to handle a month's appointments on an index card (or equivalent) to having to having to keep track of tasks and meetings in at least 3 time zones, and Chandler gives me enough flexibility and power to be able to do this without getting in the way.
ICS format
I think the last time I tried to use calendars on the computer, it was before people were seriously using a standard format. So you'd spend a lot of time putting your data into one program, only to have it die a horrible death, or discover something even better and then be stuck in your old program. Not so any more the .ics format is used by (nearly) all programs and by google calender so you can subscribe and sync calendars to your hearts content and it will all work. In all of your programs. Which means, you don't need to chose the ideal calendar program, as long as it supports .ics files.
iCal
I've had a pretty tortured relationship with iCal, Apple's stock Calendar program. In previous versions of the OS it used to be really crappy. And while it's much better now, there's nothing special about it, and it's just a bit too hard to use it to enter events, and it's task management is farcical.
Having said that it looks really good. Before you laugh at me and call me an apple fanboy allow me to be clear: data visualization is 60%-75% of a good calendar program (with the rest being performance and data entry/manipulation). The whole point is to be able to see what's going on throughout your day/week at a glance. Good visuals are key.
The great thing, is that with Chandler Hub / Google Calendars and the .ics format, you can use both programs and still keep all your data together pretty seamlessly
Ideals
Like I mentioned earlier, I'm open to hear what other people use. At least for the moment I'm reasonably happy with what I have. It might be nice to have better command line access to be able to quickly review upcoming appointments and enter new tasks, but that's mostly a pipe dream. Is there something I should be looking for that I don't know? Other cool OSS projects that I've missed?
Onward and Upward!