List Filters and Recent Activity

When a task list is selected, the right panel provides you with some statistics.

Links for added and estimated/not estimated tasks work as filters and you can click them to see appropriate tasks.
Below it is noted, what is the total amount of estimated time, how many tasks are not estimated and how many hours are logged.
Besides described filters, Scheduled list has a number of custom date filters displayed above the list:

All tags displayed for tasks in the task lists can act as filters if you click on them.
When a non-personal task list is selected the right panel also displays a recent activity list for all tasks of the list: