<p>Robert - you're talking to geeks - not many of us have enough of a life to need a calendar in the first place :)</p>
<p>Seriously, though, I've started to look at Google's calendar (online therefore accessible everywhere) previously I've dabbled with the KDE "PIM", or personal information manager/suite (integrates kmail and the native KDE calendar) Thunderbird has "lightning" as their calendar, which I've toyed with as well.</p>
<p>One thing that is nice about Google's calendar is that it can take a feed from other websites or data sources and integrate the results all in one place. You could, for instance, create one calendar account that imports the calendars of everyone on a team or project, then see at a glance when you could schedule meetings.</p>
<p>You can also embed a google calendar into other websites (I've done this with the SGVLUG calendar - go take a look)</p>