We began by identifying credible PIM suites to investigate. The list below is extracted mainly from these sources, minus uninteresting items, and sorted approximately in order of preference.
Includes mail storage, indexing, filtering (anti-spam) and presentation via IMAP or via the web. Plus contacts, calendar, tasks and notes. It has an instant message component. The facility for organizing and searching mail is particularly impressive. It is sort of open source but has a paid version that includes interfaces to Microsoft Exchange and other proprietary groupware. This suite has been picked by the UCLA Physical Sciences Division as a more acceptable alternative to Microsoft Exchange. Installation experience at the Mathematics Department has been troublesome, in that it wants to take over the entire LDAP and SMTP infrastructure and resists hacks to keep it in its cage. That was the motivation for writing this document.
Includes mail reading (but not indexing), contact list, calendar, task list, notes. The mail is stored on and delivered from a separate IMAP server. Open source, web presentation, written in PHP. Actively maintained. This suite is installed on Mathnet and while the webmail service is very popular, the other functions have not gained traction. A major problem is the lack of shared calendars and contacts. (On this, see the discussion elsewhere of Kolab, which is the server component of Horde.)
Sunbird is a standalone app; Lightning is a plugin for both Firefox
and Thunderbird. It supports calendars (not contacts or tasks). The
PIM objects are stored locally (SQLite), though the client can talk to a
server using CalDAV or WCAP protocols. File extension
iCal format (RFC 2445).
This is a PIM framework for KDE with components such as KMail and KAddressBook. Open source. To use it, you pretty much have to commit to KDE, which is not a problem for the Math Department since KDE is popular, but is a problem at home. Address book uses a D-Bus protocol to serve co-located clients; vCard in and out. Normal use would be local single user, but the article says you can also use the Kolab net server.
Open source (GPL), official PIM suite of Gnome. Serves e-mail, calendar, contacts, and tasks. Imitates Microsoft Outlook. Supports iCalendar, full-text indexing of e-mail, etc. Can talk to older Microsoft Exchange (but not 2007 and 2010), and to Novell GroupWise. Sync to phones and PDAs using gnome-pilot or OpenSync. Runs on desktop Linux; appears to have a Windows port; formerly on Mac (but no longer works). Jimc believes that it's a single-user service running on the machine where the user is logged in.
An old (pre-1987) BBS engine which initially I passed over because of its strange provenance, feature set and possibly inimical license conditions. However, it has been revamped for modern UNIX OS's, and it turns out to be under GPL. It also turns out to be originally by Jeff Prothero, an old acquaintance of mine. Content resides on the server. Includes server engines for a number of protocols including SMTP, IMAP, POP3, Sieve, GroupDAV, XMPP, and (apparently) HTTP. All of them support OpenSSL (except currently broken in XMPP). I knew little about this software before, but it looks to be worth investigating.
An MIT project to apply Semantic Web Technology to a PIM suite.
This is an Emacs editing mode and ships with Emacs. For PIM its major use-case is task lists.
Open source. Cross platform. Imitates Lotus Agenda. Does task
lists and calendars. Uses
free-form PIM object structure.
Has clients for Android and iPhone. Includes a server. Despite initial
buzz, the project was not fully finished and may not be actively
This article discusses just the calendar component, though there are also closely related contact list and mail applications and services. Task list has recently been added (2009). The server belongs to Google. Ownership of the data is not clear. The client code is Java executed by any capable web browser; it is not exactly open source, though Google can't keep the user from inspecting it. Uses iCalendar format. Calendars can be shared. Can sync with local calendar apps on Android, Blackberry, iPhone, Palm, Win Mobile, Microsoft Outlook, Apple's iCal (CalDAV protocol). Reminders sent by eMail or SMS; new events can be added via SMS.
The company owns the server. On the client it uses Google Gears to cache the content. It's mainly a task list, but is said to also include a calendar.
It is mainly a mail reader, but it includes support for calendars, task lists, contacts and notes. It can use local single-user storage, or it can talk to a Microsoft Exchange server. Third party applications allow sync with Blackberry, Android and Windows Mobile. The API is public so custom apps are feasible.
For Windows, costs $45.