PTIMG and most other games sites are blocked by our fun and friendly firewall. 'Please contact your administrator if you need to go on this site for work purposes'. Blah.
The best I can manage is looking at email notifications and drawing little diagrams of chess boards in my office, whilst looking studious and productive.
This strategy has in fact improved my game play, as I cannot make any moves, so I am still considering my move long after I would have usually clicked on the red button.