title_body: How do they get beer so strong?
upvoted_answer: Primarily through the use of freeze distillation.   After the beer is brewed, using the normal process, the temperature is brought down below the freezing point of water, but above the freezing point of alcohol, so some portion of the water in the beer freezes into ice and can then be removed.  What remains has a far higher concentration of alcohol than what can be achieved via brewing alone.  
  
  Some beers such as Sam Adams Utopias do attain quite high levels of alcohol through the use of carefully engineered strains of yeast, though nothing like the percentages in the beers you list...Only in the high 20s ABV.  Beyond that point, we haven't yet cultivated yeast that can live and continue to produce alcohol so cheating, if you will, is required.