Add-ons

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.

AutoPager automatically loads next pages when you reach the end of a page. It works on a ton of sites,Google,Yahoo..
It works well with most other add-ons adblock plus, WOT and most of the greasemonkey scripts.
You can also try AutoPagerLite.