How do I wake up Dr. Fred?

Hint 1 of 6:

First, wait until he's out of the control of the IRS.

Hint 2 of 6:

You should remember what kept Dr. Fred awake all of these weeks.

Hint 3 of 6:

The same thing will wake him up now.

Hint 4 of 6:

That's coffee -- the kind with caffeine.