Mozilla Lightning is a calendar add-on for the Mozilla Thunderbird e-mail application. Mozilla Lightning, more accurately, is an integration of Mozilla Sunbird, a stand-alone calendar, and the Thunderbird e-mail application. The integration of the calendar makes Thunderbird into more of a PIM(Personal Information Manager) than a standard e-mail application.

Lightning offers the usual assortment of features one would expect. These include making recurring appointments, easily adding regional holidays, setting appointments, etc. However, it doesn’t yet integrate as well as one would hope with Thunderbird. One thing that is still on the agenda for the Lightning development team is better integration of the calendar with Thunderbird contacts. The Lightning team admits that it is still in the development phase, so the lack of tight integration can be understood.

The Thunderbird e-mail client is actually quite good. It has many excellent features, and integrates very easily with Gmail.

If your looking for a PIM that will not break the bank, and don’t mind it not being fully integrated yet, give Mozilla Lightning a try. At the very least, it is a project to keep an eye on as it matures.