title_body: Are there any good uses for beer that has sat in my growler for too long?
upvoted_answer: Supposedly washing your hair with it has some nice effects,
  and people have found other creative uses: 
  How to make good use of flat, leftover beer from your Christmas party.
  
  However, if it is only a few days old and has been in the fridge, it's unlikely that it's done much more than go completely flat, so any use that doesn't require it to be carbonated would be fitting. -- I'd go for the bread.