Add-ons

DownThemAll! by Nils Maier, Federico Parodi, others

The first and only download manager/accelerator built inside Firefox!

Collector's Note 多线程下载利器！

User Agent Switcher by chrispederick

The User Agent Switcher extension adds a menu and a toolbar button to switch the user agent of a browser.

ReminderFox by Tom Mutdosch, Daniel Lee, others

ReminderFox displays and manages lists of reminders and tasks. ReminderFox uses easy-to-use lists with warnings/alarms to remind you of all your important appointments.
Synchronize ReminderFox with other calendars as well.

Collector's Note 备忘提醒好工具！

Gmail Manager by Todd Long

The original Gmail notifier for multiple accounts. Allows you to receive new mail notifications along with viewing account details including unread messages, saved drafts, spam messages, labels with new mail, space used, and new mail snippets.

Collector's Note Gmail 多账户提醒工具！

Mozilla Labs - Jetpack Prototype by Mozilla Labs

Jetpack Prototype is an experiment in making it easy to build Firefox add-ons using common web technologies.

Collector's Note Firefox新版插件管理器！