The Overflow tag was inspired by this question:
In that question the top rated answer made a strong case that some of the tabs would be more interesting to more users than others. In that case a More... style solution was perfectly OK.
In other circumstances, giving more prominence to the important actions and less to the less important ones both saves space and helps guide the user without forcing them to some action to reveal more:
Overflow is a recurring theme in UI design. How do you cope when there is more than will fit in your design? One approach (see for example How do you deal with unusually long labels? and How To Display Too Much Data) is to trade width for height:
or trading width for height in a table:
Making text shorter,
by better microcopy
abbreviations - 1,700,000 becomes 1.7m,
Other solutions have replaced figures by sparklines, or explored overlaid figures on a bar graph ( Labeling a multi-layered bar graph ) so that you don't need space for both the figures and the graph.
Creating an Overflow Question
When creating an 'Overflow' question, you are encouraged to use a title like 'XYZ Overflow: How do I ...'. In the question try to be clear about the scope for losing items entirely or hiding them behind some action - often suggested solutions will be to attempt to entirely eliminate items that are taking space.