Do you know the easiest way to enter timesheets with TFS?

Timesheets have always been the bane of developers, with them trying every excuse under the sun to avoid them and project managers trying everything to convince them to enter them.

The main problem is timesheet entry is often difficult, time consuming and requires double entry (e.g. into different systems TFS and invoicing system).

Project Server 2013 offers a solution that integrates with TFS work items.