Matthew van de Werken: 
  Probably the most common place for the moisture to seep 
  in is through the toe. A popular remedy for this is to 
  cover the toe with "Shoo-Goo", which is a silicon-like 
  substance that dries hard (like a tennis-shoe sole). 
  It's designed for replacing holes in soles of shoes, 
  hence the name, but it works really well on the toe of 
  a bat. The only caveat I have for its use is that it 
  makes the toe of the bat a bit grippy, so you can be 
  running, sliding the bat, and it grips and stops, 
  which is not desirable!