I love the Stack Exchange network, but I often find myself procrastinating by looking at the most recently updated questions on the sites I visit most. Those questions are rarely (if ever) relevant for the task at hand, and are potentially harmful to my productivity. Stack Exchange has a reputation system with encourages people to give a good answer rapidly — if I wait answering until the evening, I have lost a chance to get a big reputation gain. A higher reputation gives personal pride and privileges on the network.
Now how can I prevent myself from browsing to irrelevant Stack Exchange network sites during working hours over and over again? Although a couple of sites may be relevant, asking and answering on Travel and Outdoor are certainly not helping me toward my PhD in any way.
Related but different: How to use the second brain of the Stack Exchange network in a productive way?
P.S. I think this question belongs on the main site, not on meta.