The Grate Drain Maze is a mini-game in Pajama Sam 2: Thunder and Lightning Aren't So Frightening.
This is the maze of drainpipes Sam finds when he pops the grate near the Sun Machine to help Wingnut escape. Sam must crawl through the pipes to get to Wingnut and then help him out before they can fix the Sun Machine. To help Sam find his way, look for the pipe openings with the flashing white outline. When more than one is highlighted, you'll really have to concentrate -- only one is right!