By default, Sunbird sets the alarm time before events and tasks to be fifteen minutes. For most tasks in the office, I find this to be too much warning, so I end up using snooze a lot since I never remember to set the alarm time when I am creating new tasks and events. Turns out it's pretty easy to set the default alarm time in Sunbird to shorter, like 5 minutes. To do this go to Sunbird -> Preferences in the menu bar (this is how it's done on the Mac, not sure how to get to Preferences on other operating systems... but just get there). Once the Preferences window is open, select the Alarms tab. Near the bottom of the window you can set separate default alarm times for both events and tasks to any number of minutes, hours, or days that you want.