Composers that were awake when they weren't sleeping.

[Dr. Dread]

 0:)

[Elgarian]

All of them, except for Gluck, who was asleep when he wasn't awake.

[Brian]

When Telemann wasn't sleeping, he was dead.

Brahms, by contrast, was a zombie. When he wasn't sleeping, he was undead.

[DavidW]

When did they pry open their third eye?

[Dana]

Wagner - he was constantly engaged in the act of self-worship, regardless of whether or not he was composing at the time.