Ask HN: How do I ask for a raise?
In my experience, by far the best way to get a raise is to find a new job that you think you will like as much or more than your current job and take it.  In addition to the monetary benefits, this will open the door to meeting new people and take on new responsibilities.  I've never regretted doing this, and more than once that action gave my overall career trajectory a huge boost, even when I already thought I was happy (which was the case most of the time).