The giant Kumbhakarna was a formidable sleeper.

He was a fearsome warrior of Hindu legend.  He rested his head on a mountain and his snores rattled the heavens.  When the armies of evil needed him in battle they found that waking Kumbhakarna was a battle of its own. 
All of them had to sting him with lances.  Blarring horns and torrents of cold water was all that could rouse him.